Function for 'does matrix contain value X?'

Question

Is there a built in MATLAB function to find out if a matrix contains a certain value? (ala PHP\'s in_array())

Answer 1

For floating point data, you can use the new ismembertol function, which computes set membership with a specified tolerance. This is similar to the ismemberf function found in the File Exchange except that it is now built-in to MATLAB. Example:

>> pi_estimate = 3.14159;
>> abs(pi_estimate - pi)
ans =
   5.3590e-08
>> tol = 1e-7;
>> ismembertol(pi,pi_estimate,tol)
ans =
     1