Floating point subtraction rounding error (NOT display error)

2007-12-13 Thread Keflavich
Hey, I have a bit of code that died on a domain error when doing an arcsin, and apparently it's because floating point subtraction is having problems. I know about the impossibility of storing floating point numbers precisely, but I was under the impression that the standard used for that last dig

Re: Floating point subtraction rounding error (NOT display error)

2007-12-13 Thread Keflavich
Thanks, I'll have a look at that. I'm not sure the decimal type is included in numpy, though, which is what I'm using. It doesn't show up in their documentation, at least. Adam On Dec 13, 3:39 pm, [EMAIL PROTECTED] (Aahz) wrote: > In article <[EMAIL PROTECTED

Re: Floating point subtraction rounding error (NOT display error)

2007-12-13 Thread Keflavich
n rounding code, but I figured something of that sort must already exist. Thanks though, Adam On Dec 13, 3:50 pm, Keflavich <[EMAIL PROTECTED]> wrote: > Thanks, I'll have a look at that. I'm not sure the decimal type is > included in numpy, though, which is what I&#x

Re: Floating point subtraction rounding error (NOT display error)

2007-12-13 Thread Keflavich
Solved: used round(number,12) in this case for all of the operands of my arcsines. Not pretty, but at least VIM made it easy... Thanks for the help, Adam On Dec 13, 4:01 pm, Keflavich <[EMAIL PROTECTED]> wrote: > The decimal package isn't what I'm looking for - I don't

Re: Floating point subtraction rounding error (NOT display error)

2007-12-13 Thread Keflavich
On Dec 13, 5:52 pm, Steven D'Aprano <[EMAIL PROTECTED] cybersource.com.au> wrote: > On Thu, 13 Dec 2007 14:30:18 -0800, Keflavich wrote: > > Hey, I have a bit of code that died on a domain error when doing an > > arcsin, and apparently it's because floating point sub

Re: Floating point subtraction rounding error (NOT display error)

2007-12-14 Thread Keflavich
On Dec 14, 2:57 am, "Nikos Vergas" <[EMAIL PROTECTED]> wrote: > > Solved: used round(number,12) in this case for all of the operands of > > my arcsines. Not pretty, but at least VIM made it easy... > > You might have the same problem though: > > >>> round(1.0003401032523500235,13) > 1.0003

Re: Floating point subtraction rounding error (NOT display error)

2007-12-14 Thread Keflavich
On Dec 14, 8:28 am, Carl Banks <[EMAIL PROTECTED]> wrote: > On Dec 13, 6:20 pm, Keflavich <[EMAIL PROTECTED]> wrote: > > > Solved: used round(number,12) in this case for all of the operands of > > my arcsines. Not pretty, but at least VIM made it easy... > > &

Compiling 64 bit python on a mac - cannot compute sizeof (int)

2009-07-03 Thread Keflavich
I'm trying to compile a 64 bit version of python 2.6.2 on my mac (OS X 10.5.7), and am running into a problem during the configure stage. I configure with: ./configure --enable-framework=/Library/Frameworks --enable- universalsdk MACOSX_DEPLOYMENT_TARGET=10.5 --with-universal-archs=all - with-read