defining a vector with vector of indices

Hi all

I have a vector zero of size M called A, also I have another vector of size 4 that its arrays are integers among 1 to M called B. now I want to put some values in arrays of A with indeces in B, I.e I want to put values in 4 place of A, that these places are defined via B, for instace:

A=zeros(8,1), and B=[ 1 3 4 5], I want to put some defined numbers in positions 1, 3, 4 and 5 of A, how I can do that?

is there anyone to help me?

Thank you

Answer 1

[Matt J]

    A(B)=whatever

[ss]

thank you very much Matt

[ss]

matt if we have a matrix and we want to change the position of its array, rows and columns simultaneously, using two index vector B1 and B2, how can we use this command, i.e for instance u=[u11 u12 u13 u14;u21 u22 u23 u24;u31 u32 u33 u34;u41 u42 u43 u44]; B1=[1 4 3 2] B2=[3 2 1 4](B1 and B2 themselves are columns of a matrix) such that B1 is used for changing rows and B2 for changing columns, so u would be u=[u13 u12 u11 u14;u43 u42 u41 u44;u33 u32 u31 u34; u23 u22 u21 u24] thanks

Answer 2

[Andrei Bobrov]

A(B) = C;

here C - with size(C) = [1,1] or numel(C) == numel(B)

[ss]

yes, this works, thank you very much Andrei