How to define values in a vector as NaN ?

Hello,

I have a variable A that is 2x3 (x and y values) and variable B that is 2x2 (also x and y values). B actually corresponds to some of the x,y pairs in A. I would like to replace the pairs in A that correspond to those in B by NaN.

A = [1 2 3; 4 5 6];
Ax = A(1,:);
Ay = A(2,:);

B = [2 3; 5 6];
Bx = B(1,:);
By = B(2,:);

Ay(By) = NaN %this is multiplying instead of redefining --> not what I want 
Ax(By) = NaN %same here
A = [Ay;Ax]

My goal is to have A = [1 NaN NaN; 4 NaN NaN].

Can anyone help please ?

Answer 1

[Star Strider]

Try this (using ismember) —

A = [1 2 3; 4 5 6];
B = [2 3; 5 6];
C = ismember(A,B)

C = 2×3 logical array
   0   1   1
   0   1   1

A(C) = NaN

A = 2×3

1 NaN NaN 4 NaN NaN

.

[meryem berrada]

That was perfect, thank you so much !

[Star Strider]

As always, my pleasure!

.