Remove a subset matrix from another matrix

Suppose I have a certain matrix A in form

       28 77 145 127
       29 77 166 877
       30 77 176 822
       31 77 232 188
       28 78 252 611
       29 78 222 112
       30 78 236 211
       31 78 122 122

where the first two columns are lat and lon resp and the next two are data and another matrix B

       28 78 252 611
       29 78 222 112

I need to condition on the lat and lon and remove matrix B from matrix A. I could do this with for loop, I need to do it without looping if possible

Answer 1

[Image Analyst]

Try this:

A=[...
  28 77 145 127
  29 77 166 877
  30 77 176 822
  31 77 232 188
  28 78 252 611
  29 78 222 112
  30 78 236 211
  31 78 122 122]
B=[...
  28 78 252 611
  29 78 222 112]

[ia, ib] = ismember(A, B, 'rows')
A(ia, :) = []

[Sourangsu Chowdhury]

thank you!