MATLAB: Help to understand a strange behaviour

Question

WTF is the following: (noticed ocationally)

>> clear

>> sind(30)

ans =

   -0.8660

>> whos

Name      Size            Bytes  Class     Attributes
ans       1x1                 8  double

after restart:

>> sind(30)

ans = 0.5000

(R2010b)

Answer 1

I asked Google for "Matlab bug sind" and found:

See: Answers: bug-in-matlab-2010b-trig-functions.

My conclusion: Ask MathWorks for a bugfix of your version. It is easy to insert a workaround as M-file in your toolbox folder:

function Y = sind(X)
Y = sin(X * 0.017453292519943295769236954843959);