cotd — cotangent
y=cotd(x)
The entries of y
are the cotangents of the
corresponding entries of x
supposed to be given in
degree. t=cos(x)./sin(x)
. For entries equal to
n*180
with n
integers the results
are infinite, whereas cotg(n*%pi)
is large but finite
because %pi
cannot be represented exactly. For entries
equal to n*90
with n
integers and
odd the results are exactly 0.