AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

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Judd
April 18, 2009 12:41AM
FYI,

I think there's a problem with ccalc's atan2 when the second argument is zero. atan2(1,0) should yield pi/2, but:

ccalc 'atan2(1,0)'
1.0
ccalc 'atan2(-1,0)'
-1.0
ccalc 'atan2(1,0.000000001)'
1.570796
ccalc 'atan2(1,-0.000000001)'
1.570796
ccalc 'atan2(-1,0.000000001)'
-1.570796
ccalc 'atan2(-1,-0.000000001)'
-1.570796

It doesn't seem to be platform or compiler specific. I was able to test

AFNI_2008_07_18_1710
[[Precompiled binary linux_xorg7_64: Apr 9 2009]]
[[Precompiled binary solaris29_suncc_64: Oct 23 2008]]
[[Precompiled binary macosx_10.4_Intel: Jul 30 2008]]


--judd
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Subject Author Posted

ccalc atan2 bug

Judd April 18, 2009 12:41AM

Re: ccalc atan2 bug

rick reynolds April 20, 2009 04:47PM

Re: ccalc atan2 bug

Judd April 21, 2009 09:24AM

Re: ccalc atan2 bug

Judd April 21, 2009 12:00PM

Re: ccalc atan2 bug

rick reynolds April 21, 2009 12:15PM

Re: ccalc atan2 bug

rick reynolds April 30, 2009 05:12PM