errors in matlab gui

What mean this error?

??? Subscript indices must either be real positive integers or logicals.

Error in ==> b1>pushbutton1_Callback at 102 A(x,y)=B(x,y)

Answer 1

[Walter Roberson]

It means that one of the values in x or y is 0, or negative, or has a fractional component and is not exactly an integral value.

Note that if you computed x or y, then you might have suffered from round-off. See http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F