Create an array based on the values in two other arrays

Hello, I have an array A(300x1) where the numbers vary between 1 and 198 in no particular order and some rows are nan other rows are repeated. Another array B(198x2) has in the first column 1:198 sorted in order and in the second column specific values for each row. I need to create an array C having the same size as A (300x1) however having the values from column 2 of array B where column 1 of B matches the value in array A. Example, if row 1 of array A is 90, i want row 1 in array C to have the value from column 2 of B where column 1 is 90 (row 90 in B).

Simplified example:

A [3 B[1 , 0.25 C[0.66

3 2 , 0.5 0.66

nan] 3 , 0.66 nan]

4 , 0.76]

Answer 1

[Voss]

A = [3; 3; NaN];
B = [1 0.25; 2 0.5; 3 0.66; 4 0.76];

C = NaN(size(A));
[ism,idx] = ismember(A,B(:,1));
C(ism) = B(idx(ism),2);

disp(C);

    0.6600
    0.6600
       NaN

Reference: https://www.mathworks.com/help/matlab/ref/double.ismember.html

[Ziad Sari El Dine]

Perfect, thanks.

[Voss]

You're welcome!