Re: Passing arguments to & executing, a python script on a remote machine from a python script on local machine
On Thursday, September 20, 2012 10:39:28 AM UTC+5:30, Chris Angelico wrote: > On Thu, Sep 20, 2012 at 2:27 PM, Steven D'Aprano > > wrote: > > > On Wed, 19 Sep 2012 12:46:33 -0700, ashish wrote: > > > > > >> 2. I have a python script, local.py, running on local which needs to > > >> pass arguments ( 3/4 string arguments, containing whitespaces like > > >> spaces, etc ) to a python script, remote.py running on remote (the > > >> remote machine). > > > > > > If 3/4 of the arguments are strings, what sort of objects are the other > > > 1/4? Sorry for the confusion Steven. There are 3 or 4 arguments, all of which are strings. > > > > I understand the OP as meaning "three or four string arguments". Yup, that's what i meant. > > > > ChrisA -- http://mail.python.org/mailman/listinfo/python-list
Re: How to send email programmatically from a gmail email a/c when port 587(smtp) is blocked
On 19/09/2012 20:12, ashish wrote: Folks, I asked the same query on the python tutor mailing list. The responses i received are here : http://thread.gmane.org/gmane.comp.python.tutor/77601 Mark, There is nothing wrong in asking a query on multiple forums. Poeple on the tutor list, may not be part of comp.lang.python & subscribers to comp.lang.python And you've done exactly the same thing with another question. So there are two sets of answers on two mls/ngs that are completely unconnected except that I amongst others know that they exist. If you had to ask on both, why not post to both in one hit? -- Cheers. Mark Lawrence. -- http://mail.python.org/mailman/listinfo/python-list
Re: Installing Pip onto a mac os x system
On 20/09/12 03:32:40, John Mordecai Dildy wrote: > Does anyone know how to install Pip onto a mac os x ver 10.7.4? > > Ive tried easy_instal pip but it brings up this message (but it doesn't help > with my problem): > > error: can't create or remove files in install directory > > The following error occurred while trying to add or remove files in the > installation directory: > > [Errno 13] Permission denied: > '/Library/Python/2.7/site-packages/test-easy-install-1820.write-test' > > The installation directory you specified (via --install-dir, --prefix, or > the distutils default setting) was: > > /Library/Python/2.7/site-packages/ > > Perhaps your account does not have write access to this directory? If the > installation directory is a system-owned directory, you may need to sign in > as the administrator or "root" account. If you do not have administrative > access to this machine, you may wish to choose a different installation > directory, preferably one that is listed in your PYTHONPATH environment > variable. > > For information on other options, you may wish to consult the > documentation at: > > http://peak.telecommunity.com/EasyInstall.html > > Please make the appropriate changes for your system and try again. > > Thing is I am the Administrator of the computer In that case, you should be able to do sudo easy_instal pip This will ask your login password, and then run "easy_instal pip" with so-called "root" privileges. > and can use all of the folders on the mac computer. You may be able to view them, but I doubt that you can add new files to folders like, say, /Library/Python . Hope this helps, -- HansM -- http://mail.python.org/mailman/listinfo/python-list
Re: How to get the list of all my open file(descriptor)s and locks?
On 20/09/12 05:11:11, Chris Angelico wrote:
> On Thu, Sep 20, 2012 at 7:09 AM, Ian Kelly wrote:
>> You could do:
>>
>> os.listdir("/proc/%d/fd" % os.getpid())
>>
>> This should work on Linux, AIX, and Solaris, but obviously not on Windows.
On MacOS X, you can use
os.listdir("/dev/fd")
This might work on other OSes.
> I'm not sure how cross-platform it is, but at least on Linux, you can
> use /proc/self as an alias for "/proc/"+os.getpid() - worth a try,
> might make your code a bit easier to read.
>
> It's documented as useful when you don't know the PID yet (eg telling
> a process to read the file /proc/self/fd/0 to force it to use stdin).
At least on Linux, Solaris and MacOS X, you shouldd use /dev/stdin,
which is a symlink to whatever the official name is.
"/dev/stdin" is more readable and more portable than the official name.
> So I'm confident enough to recommend testing it. :)
Testing such things is the best way to learn.
Hope this helps,
-- HansM
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[Q] How to exec code object with local variables specified?
Hi,
Is it possible to run code object with local variables specified?
I'm trying the following code but not work:
def fn():
x = 1
y = 2
localvars = {'x': 0}
exec(fn.func_code, globals(), localvars)
print(localvars)
## what I expected is: {'x': 1, 'y': 2}
## but actual is: {'x': 0}
Python: 2.7.3
OS: MacOS X
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makoto kuwata
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Re: Programming Issues
On 09/19/2012 07:01 PM, Nathan Spicer wrote: > Dave, > You sent this response privately, which isn't the way the mailing list works. Private responses are good for thank-yous and for personal remarks of no interest to others. But you're short-circuiting the helping process if you don't let everyone else see what you're saying here. I'll forward my response to the list, so others can jump in. You also top-posted, rather than putting your remarks after what you're quoting. > I'm running Python 3.2. I think doing raw input is what the instructor is > looking for. What version of Python does the instructor think you're using? raw_input is not in Python 3.2, being renamed to input(). The 2.x logic of input() is fortunately gone, as it was quite unsafe. > I know a need to do a loop, but the problem is i don't know ho > to do this. An open-ended loop can be done with the while statement. What I mean by open-ended is that you have no way of predicting how many times it will loop, because it depends on data you don't have ahead of time. The other type of loop is the for loop, where the loop will normally progress till it processes all items in a sequence. A while loop might look something like: def ask_user(): amount = get_amount() while amount != 0: do_some_stuff(amount) amount = get_amount() print "done with program" # And your top-level code might look something like: if __name__ == "__main__": ask_user() If that makes sense to you, then write the functions that this one calls. If you don't understand this loop, then ask us to elaborate. And if you don't understand what this while statement itself does, ask your professor. > There is no code, because i'm not sure how or what to write. So > far we've done simple inputs. Are you aware of any examples similar to my > problem, that i could look at and possibly base my program accordingly? > > Thanks, > Nathan > -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: [Q] How to exec code object with local variables specified?
Makoto Kuwata wrote:
> Is it possible to run code object with local variables specified?
> I'm trying the following code but not work:
>
> def fn():
>x = 1
>y = 2
> localvars = {'x': 0}
> exec(fn.func_code, globals(), localvars)
> print(localvars)
> ## what I expected is: {'x': 1, 'y': 2}
> ## but actual is: {'x': 0}
>
> Python: 2.7.3
>>> loc = {}
>>> exec("x = 1; y = 2", globals(), loc)
>>> loc
{'y': 2, 'x': 1}
However, this won't work with the code object taken from a function which
uses a different a bytecode (STORE_FAST instead of STORE_NAME):
>>> import dis
>>> def f(): x = 1
...
>>> dis.dis(f)
1 0 LOAD_CONST 1 (1)
3 STORE_FAST 0 (x)
6 LOAD_CONST 0 (None)
9 RETURN_VALUE
>>> dis.dis(compile("x=1", "", "exec"))
1 0 LOAD_CONST 0 (1)
3 STORE_NAME 0 (x)
6 LOAD_CONST 1 (None)
9 RETURN_VALUE
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Re: 'indent'ing Python in windows bat
Jason Friedman wrote:
>> I'm converting windows bat files little by little to Python 3 as I
>> find time and learn Python.
>> The most efficient method for some lines is to call Python like:
>> python -c "import sys; sys.exit(3)"
>>
>> How do I "indent" if I have something like:
>> if (sR=='Cope'): sys.exit(1) elif (sR=='Perform') sys.exit(2) else
>> sys.exit(3)
>
> Some months ago I posted what I think is a similar question in the
> Unix world: I wanted to call a small portion of Python from within a
> Bash script.
>
> Someone on this list answered (for Bash):
>
> #!/bin/bash
> command1
> command2
> python -c "if True:
> import module
> if condition:
> do_this
> else:
> do_that
> "
> command4
> # end code
>
> Perhaps something similar would work for a .bat file.
>
Provided there's only one Python block in the .bat or .cmd file then
there's no real problem; you just have to hide each language from the
other:
goto :start
"""
:start
@echo off
echo This is a CMD script
python -x %~f0 "%1"
echo Back in the CMD script
goto :eof
"""
import sys
print("Welcome to Python")
print("Arguments were {}".format(sys.argv))
print("Bye!")
You can put the Python code either before or after the triple-quote
string containing the CMD commands, just begin the file with a goto to
skip into the batch commands and end them by jumping to eof.
--
Duncan Booth http://kupuguy.blogspot.com
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Fool Python class with imaginary members (serious guru stuff inside)
I'm trying to create a class that would lie to the user that a member is in some cases a simple variable and in other cases a class. The nature of the member would depend on call syntax like so: 1. x = obj.member #x becomes the "simple" value contained in member 2. x = obj.member.another_member #x becomes the "simple" value contained in first member's another_member. So the first method "detects" that we only need a simple value and returns that. The second method "sees" that we need "member" as a class and returns that. Note that "simple type" could mean anything, from int to bitmap image. I have determined that this is possible if I sacrifice the final member reference to the __call__ override using function-call syntax: 1. x = obj.member(). The call syntax returns the simple value and the other returns the class. It is also possible if I override the __xxxitem__ methods to simulate a dictionary. However, I would like to use the "true member" access syntax if possible. So, is it possible? -- http://mail.python.org/mailman/listinfo/python-list
Re: Passing arguments to & executing, a python script on a remote machine from a python script on local machine (using ssh ?)
On 9/19/2012 12:50 PM ashish said... Hi c.l.p folks Here is my situation 1. I have two machines. Lets call them 'local' & 'remote'. Both run ubuntu & both have python installed 2. I have a python script, local.py, running on 'local' which needs to pass arguments ( 3/4 string arguments, containing whitespaces like spaces, etc ) to a python script, remote.py running on 'remote' (the remote machine). I have the following questions: 1. What's the best way to accomplish my task ? Check out http://rpyc.sourceforge.net/ -- It's reasonably lightweight and has been working well for our similar situation. Emile -- http://mail.python.org/mailman/listinfo/python-list
How to limit CPU usage in Python
Hi all, Is it possible for me to put a limit in the amount of processor usage (% CPU) that my current python script is using? Is there any module useful for this task? I saw Resource module but I think it is not the module I am looking for. Some people recommend to use nice and cpulimit unix tools, but those are external to python and I prefer a python solution. I am working with Linux (Ubuntu 10.04). Best regards. -- http://mail.python.org/mailman/listinfo/python-list
Re: [Q] How to exec code object with local variables specified?
On Thu, Sep 20, 2012 at 10:15 PM, Peter Otten <__pete...@web.de> wrote:
>
loc = {}
exec("x = 1; y = 2", globals(), loc)
loc
> {'y': 2, 'x': 1}
>
> However, this won't work with the code object taken from a function which
> uses a different a bytecode (STORE_FAST instead of STORE_NAME):
>
Is there any way to use STORE_FAST instead of STORE_NAME?
exec("string", ...) is not a solution for me.
# What is different between fn.func_code and compile("string")?
--
regards,
makoto kuwata
--
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Re: [Q] How to exec code object with local variables specified?
On 9/20/2012 7:27 AM, Makoto Kuwata wrote:
Is it possible to run code object with local variables specified?
In the way you mean that, no.
I'm trying the following code but not work:
def fn():
x = 1
y = 2
localvars = {'x': 0}
exec(fn.func_code, globals(), localvars)
The globals and locals you pass to exec are the globals and locals for
the context in which the code object runs. They have nothing to do with
the code objects local namespace.
Running exec with separate globals and locals is like running the code
within a class definition context. If you ran
def fn(): x = 1
class dummy:
fn()
dummy.x would not be defined and I presume you would not expect it to.
--
Terry Jan Reedy
--
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Re: Passing arguments to & executing, a python script on a remote machine from a python script on local machine (using ssh ?)
On Wed, Sep 19, 2012 at 12:50 PM, ashish wrote:
> 2. I have a python script, local.py, running on 'local' which needs to pass
> arguments ( 3/4 string arguments, containing whitespaces like spaces, etc )
> to a python script, remote.py running on 'remote' (the remote machine).
> 3. Has anybody been able to do this using os.system ?
>
> I tried this
import os
os.system ("ssh remoteuser@remote python remote.py arg1 arg2 arg3")
>
> This worked, but if the arguments i tried to pass, had spaces, i was not able
> to 'escape' the spaces.
Use the `subprocess` module instead (with shell=False). You then won't
need to worry about escaping.
http://docs.python.org/library/subprocess.html
Cheers,
Chris
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Re: A little morning puzzle
Here is my solution: ** Incredibly convoluted and maximally less concise solution than other offerings. ** Might be better ones though. Unlikely. Zing! -- http://mail.python.org/mailman/listinfo/python-list
Re: How to limit CPU usage in Python
On 9/20/2012 11:12 AM, Rolando Cañer Roblejo wrote: Hi all, Is it possible for me to put a limit in the amount of processor usage (% CPU) that my current python script is using? Is there any module useful for this task? I saw Resource module but I think it is not the module I am looking for. Some people recommend to use nice and cpulimit unix tools, but those are external to python and I prefer a python solution. I am working with Linux (Ubuntu 10.04). Call the external tools with subprocess.open. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: How to limit CPU usage in Python
On 9/20/2012 12:46 PM, Terry Reedy wrote: On 9/20/2012 11:12 AM, Rolando Cañer Roblejo wrote: Hi all, Is it possible for me to put a limit in the amount of processor usage (% CPU) that my current python script is using? Is there any module useful for this task? I saw Resource module but I think it is not the module I am looking for. Some people recommend to use nice and cpulimit unix tools, but those are external to python and I prefer a python solution. I am working with Linux (Ubuntu 10.04). Call the external tools with subprocess.open. I meant to end that with ? as I don't know how easy it is to get the external id of the calling process that is to be limited. I presume that can be done by first calling ps (with subprocess) and searching the piped-back output. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Fool Python class with imaginary members (serious guru stuff inside)
On 9/20/2012 9:52 AM, Jure Erznožnik wrote: I'm trying to create a class that would lie to the user that a member is in some cases a simple variable and in other cases a class. The nature of the member would depend on call syntax like so: 1. x = obj.member #x becomes the "simple" value contained in member 2. x = obj.member.another_member #x becomes the "simple" value contained in first member's another_member. x.y.z is parsed and executed as (x.y).z, so you are asking if the attribute-getter can know what will be done with the object it returns. Assuming CPython, you would have to write something that searches the Python code before compilation, the ast during compilation, or the bytecode after compilation. Much easier would be to define a union class that is a simple type with attributes and return that in the first lookup. class AttrInt(int): def __getattr__(self, name): return 'attribute' y = AttrInt(3) print(y, y.a) ### 3 attribute If x.y returns an AttrInt, it will act like an int for most purposes, while x.y.z will return whatever AttrInt.__getattr__ does and the temporary AttrInt y disappears. -- Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: How to limit CPU usage in Python
On Thu, Sep 20, 2012 at 11:12 AM, Rolando Cañer Roblejo wrote: > Hi all, > > Is it possible for me to put a limit in the amount of processor usage (% > CPU) that my current python script is using? Is there any module useful for > this task? I saw Resource module but I think it is not the module I am > looking for. Some people recommend to use nice and cpulimit unix tools, but > those are external to python and I prefer a python solution. I am working > with Linux (Ubuntu 10.04). Maximum percentage of CPU used isn't normally something you control. The only way I know of to do it involves having another process monitor the thing you want to control and sending signals to stop and start it (e.g., http://cpulimit.sourceforge.net/). Typically, you instead want to control the priority (so that higher priority apps can easily take more CPU time). That's what nice is for (http://docs.python.org/library/os.html#os.nice). If you want to limit a process in the same way that ulimit does, then the resources module is what you want (http://docs.python.org/library/resource.html#resource.setrlimit). Is there a particular reason that you'd rather have your CPU sitting idle, rather than continuing with whatever code is waiting to be run? I'm having a hard time understanding what problem you might be having that some combination of setting the nice level and imposing resource limits won't handle. -- Jerry -- http://mail.python.org/mailman/listinfo/python-list
Re: Passing arguments to & executing, a python script on a remote machine from a python script on local machine (using ssh ?)
Ismael Farfán writes:
> How about something like this:
> os.system ( 'ssh remoteuser@remote python remote.py "arg 1" "arg 2" "arg 3"' )
That won't work. You need an additional level of quoting because ssh is
also a shell so it adds another level of interpretation.
The following works:
os.system('''ssh remoteuser@remote "python remote.py 'arg 1' 'arg 2' 'arg
3'"''')
--
Piet van Oostrum
WWW: http://pietvanoostrum.com/
PGP key: [8DAE142BE17999C4]
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Re: Passing arguments to & executing, a python script on a remote machine from a python script on local machine (using ssh ?)
Chris Rebert writes: > Use the `subprocess` module instead (with shell=False). You then won't > need to worry about escaping. > http://docs.python.org/library/subprocess.html You will still need to worry about escaping because on the remote end you invoke ssh which is a shell. The obvious call: subprocess.call(["ssh", "remoteuser@remote", "python", "remote.py", "arg 1", "arg 2", "arg 3"]) won't work because ssh will break up the "arg n" strings. You need to use "'arg n'" or put the whole python command in a string like: "python TEST/testargs.py 'arg 1' 'arg 2' 'arg 3'" -- Piet van Oostrum WWW: http://pietvanoostrum.com/ PGP key: [8DAE142BE17999C4] -- http://mail.python.org/mailman/listinfo/python-list
looping in array vs looping in a dic
Hi, I have this script in python that i need to apply for very large arrays (arrays coming from satellite images). The script works grate but i would like to speed up the process. The larger computational time is in the for loop process. Is there is a way to improve that part? Should be better to use dic() instead of np.ndarray for saving the results? and if yes how i can make the sum in dic()(like in the correspondent matrix[row_c,1] = matrix[row_c,1] + valuesRaster[row,col] )? If the dic() is the solution way is faster? Thanks Giuseppe import numpy as np import sys from time import clock, time # create the arrays start = time() valuesRaster = np.random.random_integers(0, 100, 100).reshape(10, 10) valuesCategory = np.random.random_integers(1, 10, 100).reshape(10, 10) elapsed = (time() - start) print(elapsed , "create the data") start = time() categories = np.unique(valuesCategory) matrix = np.c_[ categories , np.zeros(len(categories))] elapsed = (time() - start) print(elapsed , "create the matrix and append a colum zero ") rows = 10 cols = 10 start = time() for col in range(0,cols): for row in range(0,rows): for row_c in range(0,len(matrix)) : if valuesCategory[row,col] == matrix[row_c,0] : matrix[row_c,1] = matrix[row_c,1] + valuesRaster[row,col] break elapsed = (time() - start) print(elapsed , "loop in the data ") print (matrix) -- http://mail.python.org/mailman/listinfo/python-list
"Development mode"
I am new to python and I have come across the following command and its description: >Now to be able to run the project you will need to install it and its >>dependencies. >python setup.py develop I looked up what the 'develop' argument does and found: >Extra commands: > develop install package in 'development mode' I searched for a description of 'development mode' but could not find a good description. Can anyone (very briefly) explain to me, in a sentence or two: what 'development mode' is? how 'development mode' differs from other 'modes'? why/when I would use 'development mode'? what 'development mode' does or does not allow me to do? Many thanks in advance. -- http://mail.python.org/mailman/listinfo/python-list
Re: looping in array vs looping in a dic
On 2012-09-20 19:31, giuseppe.amatu...@gmail.com wrote: Hi, I have this script in python that i need to apply for very large arrays (arrays coming from satellite images). The script works grate but i would like to speed up the process. The larger computational time is in the for loop process. Is there is a way to improve that part? Should be better to use dic() instead of np.ndarray for saving the results? and if yes how i can make the sum in dic()(like in the correspondent matrix[row_c,1] = matrix[row_c,1] + valuesRaster[row,col] )? If the dic() is the solution way is faster? Thanks Giuseppe import numpy as np import sys from time import clock, time # create the arrays start = time() valuesRaster = np.random.random_integers(0, 100, 100).reshape(10, 10) valuesCategory = np.random.random_integers(1, 10, 100).reshape(10, 10) elapsed = (time() - start) print(elapsed , "create the data") start = time() categories = np.unique(valuesCategory) matrix = np.c_[ categories , np.zeros(len(categories))] elapsed = (time() - start) print(elapsed , "create the matrix and append a colum zero ") rows = 10 cols = 10 start = time() for col in range(0,cols): for row in range(0,rows): for row_c in range(0,len(matrix)) : if valuesCategory[row,col] == matrix[row_c,0] : matrix[row_c,1] = matrix[row_c,1] + valuesRaster[row,col] break elapsed = (time() - start) print(elapsed , "loop in the data ") print (matrix) If I understand the code correctly, 'matrix' contains the categories in column 0 and the totals in column 1. What you're doing is performing a linear search through the categories and then adding to the corresponding total. Linear searches are slow because on average you have to search through half of the list. Using a dict would be much faster (although you should of course measure it!). Try something like this: import numpy as np from time import time # Create the arrays. start = time() valuesRaster = np.random.random_integers(0, 100, 100).reshape(10, 10) valuesCategory = np.random.random_integers(1, 10, 100).reshape(10, 10) elapsed = time() - start print(elapsed, "Create the data.") start = time() categories = np.unique(valuesCategory) totals = dict.fromkeys(categories, 0) elapsed = time() - start print(elapsed, "Create the totals dict.") rows = 100 cols = 10 start = time() for col in range(cols): for row in range(rows): cat = valuesCategory[row, col] ras = valuesRaster[row, col] totals[cat] += ras elapsed = time() - start print(elapsed, "Loop in the data.") print(totals) -- http://mail.python.org/mailman/listinfo/python-list
Re: Fool Python class with imaginary members (serious guru stuff inside)
On Thu, 20 Sep 2012 06:52:07 -0700, Jure Erznožnik wrote: > I'm trying to create a class that would lie to the user that a member is > in some cases a simple variable and in other cases a class. The nature > of the member would depend on call syntax like so: > 1. x = obj.member #x becomes the "simple" value contained in member > 2. x = obj.member.another_member #x becomes the "simple" value > contained in first member's another_member. Why do you hate your users so much that you want to cause them enormous difficulty with perfectly reasonable code like this? tmp = obj.member x = tmp.another_member > So the first method "detects" that we only need a simple value and > returns that. Fortunately that is impossible without nasty bytecode or AST hacks. Thank the stars that Python doesn't allow anything as badly designed as this! -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: How to limit CPU usage in Python
Am 20.09.2012 17:12, schrieb Rolando Cañer Roblejo: > Hi all, > > Is it possible for me to put a limit in the amount of processor usage (% > CPU) that my current python script is using? Is there any module useful > for this task? I saw Resource module but I think it is not the module I > am looking for. Some people recommend to use nice and cpulimit unix > tools, but those are external to python and I prefer a python solution. > I am working with Linux (Ubuntu 10.04). Hello, you have two options here. You can either limit the total amount of CPU seconds with the resource module or reduce the priority and scheduling priority of the process. The resource module is a wrapper around the setrlimit and getrlimit feature as described in http://linux.die.net/man/2/setrlimit . The scheduling priority can be altered with nice, get/setpriority or io priority. The psutil package http://code.google.com/p/psutil/ wraps all functions in a nice Python API. Regards Christian -- http://mail.python.org/mailman/listinfo/python-list
Re: looping in array vs looping in a dic
On Thu, Sep 20, 2012 at 1:09 PM, MRAB wrote: > for col in range(cols): > for row in range(rows): > cat = valuesCategory[row, col] > ras = valuesRaster[row, col] > totals[cat] += ras Expanding on what MRAB wrote, since you probably have far fewer categories than pixels, you may be able to take better advantage of numpy's vectorized operations (which are pretty much the whole point of using numpy in the first place) by looping over the categories instead: for cat in categories: totals[cat] += np.sum(valuesCategory * (valuesRaster == cat)) -- http://mail.python.org/mailman/listinfo/python-list
Re: looping in array vs looping in a dic
On Thu, Sep 20, 2012 at 1:28 PM, Ian Kelly wrote: > Expanding on what MRAB wrote, since you probably have far fewer > categories than pixels, you may be able to take better advantage of > numpy's vectorized operations (which are pretty much the whole point > of using numpy in the first place) by looping over the categories > instead: > > for cat in categories: > totals[cat] += np.sum(valuesCategory * (valuesRaster == cat)) Of course, that should have read: for cat in categories: totals[cat] += np.sum(valuesRaster * (valuesCategory == cat)) -- http://mail.python.org/mailman/listinfo/python-list
When should I use "development mode"?
I am new to python and I have come across the following command and its description: >Now to be able to run the project you will need to install it and its >>dependencies. >python setup.py develop I looked up what the 'develop' argument does and found: >Extra commands: > develop install package in 'development mode' I searched for a description of 'development mode' but could not find a good description. Can anyone (very briefly) explain to me, in a sentence or two: what 'development mode' is? how 'development mode' differs from other 'modes'? why/when I would use 'development mode'? what 'development mode' does or does not allow me to do? Many thanks in advance. -- http://mail.python.org/mailman/listinfo/python-list
Re: When should I use "development mode"?
On Thu, Sep 20, 2012 at 1:38 PM, py_lrnr wrote: > Can anyone (very briefly) explain to me, in a sentence or two: > > what 'development mode' is? > how 'development mode' differs from other 'modes'? > why/when I would use 'development mode'? > what 'development mode' does or does not allow me to do? Instead of installing the package into your site-packages, it installs a link back to the source folder. This lets you make changes to the code in the source folder which are immediately visible to Python without having to install the package again. -- http://mail.python.org/mailman/listinfo/python-list
Re: Installing Pip onto a mac os x system
Thank you Hans M. for some input. Now it shows the error of: sudo: easy_instal: command not found -- http://mail.python.org/mailman/listinfo/python-list
Re: Installing Pip onto a mac os x system
In John Mordecai Dildy writes: > Now it shows the error of: > sudo: easy_instal: command not found Try 'easy_install' instead of 'easy_instal'. -- John Gordon A is for Amy, who fell down the stairs gor...@panix.com B is for Basil, assaulted by bears -- Edward Gorey, "The Gashlycrumb Tinies" -- http://mail.python.org/mailman/listinfo/python-list
Re: Installing Pip onto a mac os x system
On Thursday, September 20, 2012 4:37:36 PM UTC-4, John Gordon wrote: > In John Mordecai > Dildy writes: > > > > > Now it shows the error of: > > > > > sudo: easy_instal: command not found > > > > Try 'easy_install' instead of 'easy_instal'. > > > > -- > > John Gordon A is for Amy, who fell down the stairs > > gor...@panix.com B is for Basil, assaulted by bears > > -- Edward Gorey, "The Gashlycrumb Tinies" Thanks John G. -- http://mail.python.org/mailman/listinfo/python-list
portable way of locating an executable (like which)
I'd like to implement the equivalent functionality of the unix command /usr/bin/which The function should work under Linux and under windows. Did anybody already implement such a function. If not, is there a portable way of splitting the environment variable PATH? Thanks for any sugestions -- http://mail.python.org/mailman/listinfo/python-list
Re: portable way of locating an executable (like which)
On 20/09/2012 22:06, Gelonida N wrote: I'd like to implement the equivalent functionality of the unix command /usr/bin/which The function should work under Linux and under windows. Did anybody already implement such a function. Searching found nothing obvious to me :( If not, is there a portable way of splitting the environment variable PATH? With os.sep ? Thanks for any sugestions -- Cheers. Mark Lawrence. -- http://mail.python.org/mailman/listinfo/python-list
Re: portable way of locating an executable (like which)
On Thu, Sep 20, 2012 at 5:06 PM, Gelonida N wrote:
> I'd like to implement the equivalent functionality of the unix command
> /usr/bin/which
>
> The function should work under Linux and under windows.
>
> Did anybody already implement such a function.
> If not, is there a portable way of splitting the environment variable PATH?
>
I've used the following in programs I write:
def which(program):
def is_exe(fpath):
return os.path.exists(fpath) and os.access(fpath, os.X_OK)
fpath, fname = os.path.split(program)
if fpath:
if is_exe(program):
return program
else:
for path in os.getenv("PATH").split(os.pathsep):
exe_file = os.path.join(path, program)
if is_exe(exe_file):
return exe_file
return None
IIRC, I adapted it from StackOverflow. I know it works on Linux and Mac OS
X, but not sure about windows (since I don't know if PATH works the same
way there).
HTH,
Jason
--
http://mail.python.org/mailman/listinfo/python-list
Re: portable way of locating an executable (like which)
On Fri, Sep 21, 2012 at 7:47 AM, Mark Lawrence wrote:
> On 20/09/2012 22:06, Gelonida N wrote:
>>
>> I'd like to implement the equivalent functionality of the unix command
>> /usr/bin/which
>>
>> The function should work under Linux and under windows.
>>
>> Did anybody already implement such a function.
>
> Searching found nothing obvious to me :(
>
>> If not, is there a portable way of splitting the environment variable
>> PATH?
> With os.sep ?
os.sep is the directory separator, but os.pathsep may be what you
want. Between that and os.getenv('path') you can at least get the
directories. Then on Windows, you also need to check out
os.getenv('pathext') and split _that_ on the semicolon, and try each
of those as a file extension. I'm not sure whether or not Windows will
add extensions from pathext if one is given on the command line - for
instance, if typing "foo.exe" will search for "foo.exe.bat" - but the
basics are there.
Alternatively, there may be a Win32 API funct5ion that does this.
Would be worth a look.
ChrisA
--
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Re: portable way of locating an executable (like which)
On Thu, Sep 20, 2012 at 4:21 PM, Chris Angelico wrote:
> os.sep is the directory separator, but os.pathsep may be what you
> want. Between that and os.getenv('path') you can at least get the
> directories. Then on Windows, you also need to check out
> os.getenv('pathext') and split _that_ on the semicolon, and try each
> of those as a file extension. I'm not sure whether or not Windows will
> add extensions from pathext if one is given on the command line - for
> instance, if typing "foo.exe" will search for "foo.exe.bat" - but the
> basics are there.
Easy enough to test:
C:\>echo echo hello! > foo.exe.bat
C:\>foo.exe
hello!
Yup, it does. It looks like it tries it without the extension first, though:
C:\>copy c:\windows\notepad.exe foo.exe
1 file(s) copied.
C:\>foo.exe
[starts notepad]
--
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Re: portable way of locating an executable (like which)
On Fri, Sep 21, 2012 at 8:32 AM, Ian Kelly wrote:
> On Thu, Sep 20, 2012 at 4:21 PM, Chris Angelico wrote:
>> os.sep is the directory separator, but os.pathsep may be what you
>> want. Between that and os.getenv('path') you can at least get the
>> directories. Then on Windows, you also need to check out
>> os.getenv('pathext') and split _that_ on the semicolon, and try each
>> of those as a file extension. I'm not sure whether or not Windows will
>> add extensions from pathext if one is given on the command line - for
>> instance, if typing "foo.exe" will search for "foo.exe.bat" - but the
>> basics are there.
>
> Easy enough to test:
>
> C:\>echo echo hello! > foo.exe.bat
>
> C:\>foo.exe
> hello!
>
> Yup, it does. It looks like it tries it without the extension first, though:
>
> C:\>copy c:\windows\notepad.exe foo.exe
> 1 file(s) copied.
>
> C:\>foo.exe
> [starts notepad]
Well, at least it's consistent. Makes your PATH extremely sensitive,
though, easy for anyone to inject executables into it. But then, you
can already do that by putting them in the current directory, so
that's not really any different.
Jason's solution looks fine apart from the PATHEXT requirement, so if
you know you have the full filename and you don't care if the actual
command interpreter will do exactly the same, that'll do you fine.
Is this something that might want to be a function in the os module?
Particularly so if, as I suspect there might be, there's a Win32 API
function that precisely replicates the behaviour of executable
invocation. A while since I've done much Windows programming but I
think there's a SearchPath function?
ChrisA
--
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Re: portable way of locating an executable (like which)
On 09/21/2012 12:21 AM, Chris Angelico wrote:
On Fri, Sep 21, 2012 at 7:47 AM, Mark Lawrence wrote:
On 20/09/2012 22:06, Gelonida N wrote:
I'd like to implement the equivalent functionality of the unix command
/usr/bin/which
The function should work under Linux and under windows.
Did anybody already implement such a function.
Searching found nothing obvious to me :(
I was afraid so, but wanted to be sure
If not, is there a portable way of splitting the environment variable
PATH?
With os.sep ?
os.sep is the directory separator, but os.pathsep may be what you
want.
Thanks,
os.pathsep was the missing piece for portably splitting the searchpath
Between that and os.getenv('path') you can at least get the
directories. Then on Windows, you also need to check out
os.getenv('pathext') and split _that_ on the semicolon, and try each
of those as a file extension. I'm not sure whether or not Windows will
add extensions from pathext if one is given on the command line - for
instance, if typing "foo.exe" will search for "foo.exe.bat" - but the
basics are there.
For what I am doing I can even skip trying the pathexts, the ext is
already given, but good to know :-)
Alternatively, there may be a Win32 API funct5ion that does this.
Would be worth a look.
Yeah true, but ideally I'd like to avoid platform detection and
just have a generic function.
--
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Re: portable way of locating an executable (like which)
On 09/21/2012 12:04 AM, Jason Swails wrote:
Thanks a lot Jason,
I've used the following in programs I write:
def which(program):
def is_exe(fpath):
return os.path.exists(fpath) and os.access(fpath, os.X_OK)
fpath, fname = os.path.split(program)
if fpath:
if is_exe(program):
return program
else:
for path in os.getenv("PATH").split(os.pathsep):
exe_file = os.path.join(path, program)
if is_exe(exe_file):
return exe_file
return None
IIRC, I adapted it from StackOverflow. I know it works on Linux and Mac
OS X, but not sure about windows (since I don't know if PATH works the
same way there).
I'll try it, the script looks reasonably portable (using os.pathsep)
to really replicate which I had probably to add os.getenv('pathext')
as Chris mentioned.
However for my current use case this is not necessarily required.
HTH,
Jason
--
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Re: looping in array vs looping in a dic
Hi Ian and MRAB
thanks to you input i have improve the speed of my code. Definitely reading in
dic() is faster. I have one more question.
In the dic() I calculate the sum of the values, but i want count also the
number of observation, in order to calculate the average in the end.
Should i create a new dic() or is possible to do in the same dic().
Here in the final code.
Thanks Giuseppe
rows = dsCategory.RasterYSize
cols = dsCategory.RasterXSize
print("Generating output file %s" %(dst_file))
start = time()
unique=dict()
for irows in xrange(rows):
valuesRaster=dsRaster.GetRasterBand(1).ReadAsArray(0,irows,cols,1)
valuesCategory=dsCategory.GetRasterBand(1).ReadAsArray(0,irows,cols,1)
for icols in xrange(cols):
if ( valuesRaster[0,icols] != no_data_Raster ) and (
valuesCategory[0,icols] != no_data_Category ) :
row = valuesCategory[0, icols],valuesRaster[0, icols]
if row[0] in unique :
unique[row[0]] += row[1]
else:
unique[row[0]] = 0+row[1] # this 0 was add if not the first
observation was considered = 0
--
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Re: portable way of locating an executable (like which)
On 21/09/2012 00:15, Gelonida N wrote:
On 09/21/2012 12:04 AM, Jason Swails wrote:
Thanks a lot Jason,
I've used the following in programs I write:
def which(program):
def is_exe(fpath):
return os.path.exists(fpath) and os.access(fpath, os.X_OK)
fpath, fname = os.path.split(program)
if fpath:
if is_exe(program):
return program
else:
for path in os.getenv("PATH").split(os.pathsep):
exe_file = os.path.join(path, program)
if is_exe(exe_file):
return exe_file
return None
IIRC, I adapted it from StackOverflow. I know it works on Linux and Mac
OS X, but not sure about windows (since I don't know if PATH works the
same way there).
I'll try it, the script looks reasonably portable (using os.pathsep)
to really replicate which I had probably to add os.getenv('pathext')
as Chris mentioned.
However for my current use case this is not necessarily required.
HTH,
Jason
http://nedbatchelder.com/code/utilities/wh_py.html
--
Cheers.
Mark Lawrence.
--
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Re: looping in array vs looping in a dic
On 2012-09-21 00:35, giuseppe.amatu...@gmail.com wrote:
Hi Ian and MRAB
thanks to you input i have improve the speed of my code. Definitely reading in
dic() is faster. I have one more question.
In the dic() I calculate the sum of the values, but i want count also the
number of observation, in order to calculate the average in the end.
Should i create a new dic() or is possible to do in the same dic().
Here in the final code.
Thanks Giuseppe
Keep it simple. Use 2 dicts.
rows = dsCategory.RasterYSize
cols = dsCategory.RasterXSize
print("Generating output file %s" %(dst_file))
start = time()
unique=dict()
for irows in xrange(rows):
valuesRaster=dsRaster.GetRasterBand(1).ReadAsArray(0,irows,cols,1)
valuesCategory=dsCategory.GetRasterBand(1).ReadAsArray(0,irows,cols,1)
for icols in xrange(cols):
if ( valuesRaster[0,icols] != no_data_Raster ) and (
valuesCategory[0,icols] != no_data_Category ) :
row = valuesCategory[0, icols],valuesRaster[0, icols]
if row[0] in unique :
unique[row[0]] += row[1]
else:
unique[row[0]] = 0+row[1] # this 0 was add if not the first
observation was considered = 0
You could use defaultdict instead:
from collections import defaultdict
unique = defaultdict(int)
...
category, raster = valuesCategory[0, icols],
valuesRaster[0, icols]
unique[category] += raster
--
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Re: portable way of locating an executable (like which)
On Thu, 20 Sep 2012 23:06:46 +0200, Gelonida N wrote: > I'd like to implement the equivalent functionality of the unix command > /usr/bin/which > > The function should work under Linux and under windows. Note that "which" attempts to emulate the behaviour of execvp() etc. The exec(3) manpage will explain the precise algorithm used (e.g. they skip files for which the process lacks execute permission). Also, note that the shell has built-in commands, functions, and aliases in addition to programs. The "type" built-in command performs a similar function to "which" but using the shell's semantics. On some systems, the default configuration may alias "which" to "type". On Windows, there's a host of different "execute program" interface, all with subtly different semantics: which extensions they will run, which extensions can be omitted, which paths are used (e.g. %PATH%, paths from the registry, current directory). -- http://mail.python.org/mailman/listinfo/python-list
Re: portable way of locating an executable (like which)
On 09/20/2012 06:04 PM, Jason Swails wrote:
> On Thu, Sep 20, 2012 at 5:06 PM, Gelonida N wrote:
>
>> I'd like to implement the equivalent functionality of the unix command
>> /usr/bin/which
>>
>> The function should work under Linux and under windows.
>>
>> Did anybody already implement such a function.
>> If not, is there a portable way of splitting the environment variable PATH?
>>
> I've used the following in programs I write:
>
> def which(program):
>def is_exe(fpath):
> return os.path.exists(fpath) and os.access(fpath, os.X_OK)
>
>fpath, fname = os.path.split(program)
>if fpath:
> if is_exe(program):
> return program
>else:
> for path in os.getenv("PATH").split(os.pathsep):
> exe_file = os.path.join(path, program)
> if is_exe(exe_file):
> return exe_file
>return None
>
> IIRC, I adapted it from StackOverflow. I know it works on Linux and Mac OS
> X, but not sure about windows (since I don't know if PATH works the same
> way there).
>
I don't have a Windows machine set up right now, but I believe there are
two more directories to search, besides the ones described in the PATH
variable.
One is the current directory, and the other is the Windows directory
(maybe also the xxx/system32 or something).
They don't have analogues in Linux or Mac, as far as I know.
--
DaveA
--
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Re: portable way of locating an executable (like which)
On 2012.09.20 21:31, Dave Angel wrote: > I don't have a Windows machine set up right now, but I believe there are > two more directories to search, besides the ones described in the PATH > variable. > > One is the current directory, and the other is the Windows directory > (maybe also the xxx/system32 or something). Those system directories are in the path by default. -- CPython 3.3.0rc2 | Windows NT 6.1.7601.17835 -- http://mail.python.org/mailman/listinfo/python-list
Re: Obnoxious postings from Google Groups
On 9/16/2012 8:18 AM, Ben Finney wrote: Νικόλαος Κούρας writes: Iam sorry i didnt do that on purpose and i dont know how this is done. Iam positng via google groups using chrome, thats all i know. It is becoming quite clear that some change has happened recently to Google Groups that makes posts coming from there rather more obnoxious than before. And there doesn't seem to be much its users can do except use something else. Using Google Groups for posting to Usenet has been a bad idea for a long time, but now it just seems to be a sure recipe for annoying the rest of us. Again, not something you have much control over, except to stop using Google Groups. Could this mean that Google wants all the spam posted through Google Groups to look obnoxious to the rest of Usenet that the spammers will go elsewhere? Robert Miles -- http://mail.python.org/mailman/listinfo/python-list
python idioms : some are confusing
Amongst the python idioms, how the below-mentioned make sense? ## There should be one-- and preferably only one --obvious way to do it. Although that way may not be obvious at first unless you're Dutch. --- In programming, there can be a number of ways, equally efficient, to do certain thing. ## Although never is often better than *right* now. --- How come "never" is better that "right now" ? Any thoughts?... -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
On Sep 21, 3:34 pm, Vineet wrote: > Amongst the python idioms, how the below-mentioned make sense? > ## There should be one-- and preferably only one --obvious way to do it. > --- In programming, there can be a number of ways, equally efficient, to do > certain thing. This isn't talking about your Python code as much as about Python itself. For example, in Python 2.x you can use either `open` or `file` to open a file, with `file` being a factory function for creating file objects, and `open` using it internally. In Python 3.x, `file` is no longer a built-in, as it produced a point of confusion as to which was the one obvious way to open a file. > ## Although never is often better than *right* now. > --- How come "never" is better that "right now" ? It's better to not add a language feature than it is to add it poorly, especially when you endeavour to provide backwards compatibility as much as possible within major versions. -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
On Thu, Sep 20, 2012 at 10:34 PM, Vineet wrote: > Amongst the python idioms, how the below-mentioned make sense? These aren't idioms (that term has a specific technical meaning in programming); they're *way* too abstract to be idioms. "Design principles" or "design guidelines" would be a better description. > ## There should be one-- and preferably only one --obvious way to do it. > Although that way may not be obvious at first unless you're Dutch. > > --- In programming, there can be a number of ways, equally efficient, to do > certain thing. Yes, but that brings with it the cost of having to understand/learn them all, because you'll encounter them when reading/maintaining/modifying others' code. And you'll have to evaluate them all to choose which one you should use (which might even vary from moment to moment depending on the circumstances). And you'll have to watch out for subtle variants that actually do something significantly different. Better to keep things simple in the X% of cases where the differences don't matter enough, and save those brain cycles for other, more important things. See also: the so-called "paradox of choice". Further reading: the criticisms on http://c2.com/cgi/wiki?ThereIsMoreThanOneWayToDoIt > ## Although never is often better than *right* now. > > --- How come "never" is better that "right now" ? Because "right now" is so quick that it was likely hastily hacked together and thus of poor (or at least lesser) quality. Cheers, Chris -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
I'm responding to the OP here, not to Alex, but I'm quoting his text to expand on it. :) On Fri, Sep 21, 2012 at 3:52 PM, alex23 wrote: > On Sep 21, 3:34 pm, Vineet wrote: >> Amongst the python idioms, how the below-mentioned make sense? >> ## There should be one-- and preferably only one --obvious way to do it. >> --- In programming, there can be a number of ways, equally efficient, to do >> certain thing. > > This isn't talking about your Python code as much as about Python > itself. The "it" in the zen there refers to some programming task. For instance, there's only one obvious way to increment an integer: spam += 1 Python's philosophy is to have just that, and to not trouble itself with "spam++" and "++spam" and the distinction between them. As a C programmer, I'm quite accustomed to them, and know what they mean, but not everyone does. And don't get me started on "&&" vs "and" in PHP... Python is a simpler and cleaner language for not having superfluous operators. >> ## Although never is often better than *right* now. >> --- How come "never" is better that "right now" ? > > It's better to not add a language feature than it is to add it poorly, > especially when you endeavour to provide backwards compatibility as > much as possible within major versions. The compatibility issue is the thing here. It's better to get something good now rather than dither for another fifty years, because the longer you dally, the more code will be written using third party libraries. But it's better to not put it into the standard library at all than to put in a messy API that now can't be changed because code's using it. The Zen of Python is a whole lot of tradeoffs and ideas. Several of them balance each other directly. Some, while not contradicted in the Zen itself, are still violated at times in the language and/or stdlib. They're principles, not laws, and need to be read with the understanding that people who write code are intelligent, thinking beings (though a quick look at TheDailyWTF.com proves that this is not universal). ChrisA -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
Oh I see ! On these lines mentioned by you, I can now sense the sense. Thanks. On Friday, 21 September 2012 11:22:45 UTC+5:30, alex23 wrote: > On Sep 21, 3:34 pm, Vineet wrote: > > > Amongst the python idioms, how the below-mentioned make sense? > > > ## There should be one-- and preferably only one --obvious way to do it. > > > --- In programming, there can be a number of ways, equally efficient, to do > > certain thing. > > > > This isn't talking about your Python code as much as about Python > > itself. For example, in Python 2.x you can use either `open` or `file` > > to open a file, with `file` being a factory function for creating file > > objects, and `open` using it internally. In Python 3.x, `file` is no > > longer a built-in, as it produced a point of confusion as to which was > > the one obvious way to open a file. > > > > > ## Although never is often better than *right* now. > > > --- How come "never" is better that "right now" ? > > > > It's better to not add a language feature than it is to add it poorly, > > especially when you endeavour to provide backwards compatibility as > > much as possible within major versions. -- http://mail.python.org/mailman/listinfo/python-list
Is there a public API equvalent for urllib2.parse_http_list?
I'm porting my code to python3, and found there is no parse_http_list in any module of urllib of python3. So, is there a public API equvalent for urllib2.parse_http_list? Thanks. Cosmia Luna -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
On Thu, 20 Sep 2012 22:34:48 -0700, Vineet wrote: > Amongst the python idioms, how the below-mentioned make sense? They're not Python idioms. Idioms are common pieces of code, like looping: for item in sequence: do_something What you have quoted are parts of the Zen of Python, which is deliberately named. Zen koans are notorious for being contradictory and impossible to understand. As Terry Pratchett wrote: In the second scroll of Wen the Eternally Surprised a story is written concerning one day when the apprentice Clodpool, in a rebellious mood, approached Wen and spake thusly: "Master, what is the difference between a humanistic, monastic system of belief in which wisdom is sought by means of an apparently nonsensical system of questions and answers, and a lot of mystic gibberish made up on the spur of the moment?" Wen considered this for some time, and at last said: "A fish!" And Clodpool went away, satisfied. -- (Terry Pratchett, Thief of Time) So be careful about over-interpreting the Zen of Python. Half of it is meant to followed seriously, half is meant as a joke, and half is meant as a guideline only. > ## There should be one-- and preferably only one --obvious way to do it. > Although that way may not be obvious at first unless you're Dutch. This tells us that for any task you might want to do in Python, there should be some way to do it which is obvious. It is not enough that there is some (hard to find, convoluted) way to do it, it should be obvious. And while it isn't forbidden to be two or more obvious ways, it is better if there is only one. The joke is that even this single sentence goes against its own advice. There are at least three obvious ways to put a parenthetical aside in a sentence: There should be one--and preferably only one--obvious way to do it. There should be one -- and preferably only one -- obvious way to do it. There should be one (and preferably only one) obvious way to do it. The author of the Zen deliberately choose a fourth, non-obvious way. Finally, the second line warns that although Python has many obvious ways to solve things, they may only be obvious to the creator of Python, Guido van Rossum, who is Dutch. > --- In programming, there can be a number of ways, equally efficient, to > do certain thing. The Zen refers to the philosophy that Python the language should provide an obvious way to solve a problem. The emphasis is on the *obvious* part, not the *one* part. > ## Although never is often better than *right* now. > > --- How come "never" is better that "right now" ? Solving a problem in the language -- adding a new language feature such as a keyword, new syntax, a library, etc. -- should only be done when that new feature brings more benefit than problems. But sometimes a new feature might bring more problems than benefits. In this case, it is better to *never* solve that problem *in the language* than to add a feature that solves the problem badly and causes more problems than it solves. E.g. multi-line lambdas. The problem is that once you add a feature to the language, it becomes almost impossible to remove it. You are stuck with it nearly forever, or at least for many years. So better to not add it than to be stuck with a bad feature. -- Steven -- http://mail.python.org/mailman/listinfo/python-list
Re: Storing of folder structure in SQL DB
folderid name parentid 1 cricket 0 2 india 1 3 sachin 2 4 tennis 0 5 saniamirza 4 i need coding for this table..folder id 'll automatically populate.. -- http://mail.python.org/mailman/listinfo/python-list
Re: Is there a public API equvalent for urllib2.parse_http_list?
On Friday, September 21, 2012 2:22:08 PM UTC+8, Cosmia Luna wrote: > I'm porting my code to python3, and found there is no parse_http_list in any > module of urllib of python3. > > > > So, is there a public API equvalent for urllib2.parse_http_list? > > > > Thanks. > > > > > > Cosmia Luna I'm sorry, but I found it at urllib.request.parse_http_list. But I still want to know where is a DOCUMENTED equivalent of this function, or the python team forgot to document it? Thanks. Cosmia Luna -- http://mail.python.org/mailman/listinfo/python-list
Re: python idioms : some are confusing
On Thu, 20 Sep 2012 22:52:45 -0700, alex23 wrote:
> On Sep 21, 3:34 pm, Vineet wrote:
>> Amongst the python idioms, how the below-mentioned make sense? ## There
>> should be one-- and preferably only one --obvious way to do it. --- In
>> programming, there can be a number of ways, equally efficient, to do
>> certain thing.
>
> This isn't talking about your Python code as much as about Python
> itself. For example, in Python 2.x you can use either `open` or `file`
> to open a file, with `file` being a factory function for creating file
> objects, and `open` using it internally. In Python 3.x, `file` is no
> longer a built-in, as it produced a point of confusion as to which was
> the one obvious way to open a file.
I don't think that's the reason. I think the reason is that moving the
built-in file into the _io library gives the developers a lot more
flexibility in how they handle text and binary files. E.g.:
py> open('junk', 'w')
<_io.TextIOWrapper name='junk' mode='w' encoding='UTF-8'>
py> open('junk', 'wb')
<_io.BufferedWriter name='junk'>
py> open('junk', 'wb', buffering=0)
<_io.FileIO name='junk' mode='wb'>
The open() function now can return three (or more?) types instead of
having a single built-in type handle all cases.
--
Steven
--
http://mail.python.org/mailman/listinfo/python-list
Re: Storing of folder structure in SQL DB
On Friday, September 21, 2012 11:57:05 AM UTC+5:30, santhosh.s...@gmail.com wrote: > folderid name parentid > > > > 1 cricket 0 > > 2 india 1 > > 3 sachin 2 > > 4 tennis 0 > > 5 saniamirza 4 > > > > i need coding for this table..folder id 'll automatically populate.. in asp.net or sql -- http://mail.python.org/mailman/listinfo/python-list
