On 7/23/2011 2:28 PM, rantingrick wrote:
On Jul 23, 1:53 am, Frank Millman<fr...@chagford.com> wrote:
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The problem with that is that it will silently ignore any non-zero
digits after the point. Of course int(float(x)) does the same, which I
had overlooked.
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Wait a minute; first you said all you wanted was to cast "string
floats" to integers NOW your changing the rules.
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I do not expect any non-zero digits after the point, but if there are,
I would want to be warned, as I should probably be treating it as a
float, not an int.
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Then the solution is a try:except.
py> def castit(value):
... try:
... v = int(value)
... return v
... except ValueError:
... return float(value)
...
py> castit('165')
165
py> castit('165.0')
165.0
py> castit('165.333')
165.333
py> castit('3.3')
3.3
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To recap, the original problem is that it would appear that some third-
party systems, when serialising int's into a string format, add a .0
to the end of the string. I am trying to get back to the original int
safely.
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But you also said you wanted floats too, i am confused??
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The ideal solution is the one I sketched out earlier - modify python's
'int' function to accept strings such as '165.0'.
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NO! You create your OWN casting function for special cases.
PythonZEN: "Special cases aren't special enough to break the rules."
I'll probably get flak for this, but damn the torpedoes:
def my_int(num):
import re
try:
m = re.match('^(-?[0-9]+)(.0)?$', num)
return int(m.group(1))
except AttributeError:
#raise your own error, or re raise
raise
--
Bill
--
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