difference between t and t~

function s = powersin(x)
%POWERSIN  Power series for sin(x).
%  y = POWERSIN(x) tries to compute sin(x) from its power series.
s = 0;
t = x;
n = 1;
while s+t~= s;
   s = s + t;
   t = -x.^2/((n+1)*(n+2)).*t;
   n = n + 2;
end

[John D'Errico]

Um, t~ does not exist in MATLAB. It is invalid syntax on its own. In fact, the characters "t~" only appear in your code in one place, in a test. There, the operator is ~= so the ~ is actually part of a test for inequality. It is not a separate operator applied to t in any way.

help ne

doc ne

I would strongly suggest that you start at the beginning. Read the beginning tutorials. Learn basic MATLAB syntax.