WEIRD PROBLEM: cannot find 28.88 in an array

E = 14:0.01:141;
find(E==28.88);

Please run the code above. The result is 'empty'? It's odd. Is this a bug in Matlab or my problem?

Answer 1

[Star Strider]

It’s neither a bug nor your problem. It’s a combination of the inexact representation of decimal numbers as binary floating-point numbers, and the way MATLAB calculates colon-operator-generated vectors. So you have to allow for tolerances.

This works:

E = 14:0.01:141;
idx1 = find(E<=28.88, 1, 'last');
idx2 = find(E>=28.88, 1, 'first');

Result = E([idx1 idx2])

Result =
    28.8700    28.8800