Eliminating part of arrays in matlab -

Assume that we have a 100 * 4 array.

We also have a 100 * 1 array, say 1 and 0, assuming that N1 is.

We want to create an array * 4 from the array 100 * 4, where we include only those columns for which the second array is 1.

One way to do this is through a double for the loop. Is there an easier way?

Then, we have

  A = [332 44 33 22 33 55 33 211 ..... [823 44 12 98 1] 23 32 9 11. ... .... .... ....   
 and  
  b = [0 0 0 0 0 0 ...]   
 and we want  
  c = [[332 22 ... [823 98 ... ... ... .]    
 
 
 You should use:  
  C = A (:, B == 1);