Replace arrays of a matrix with a vector

1 次查看（过去 30 天）

amin 2020-2-4

评论： amin 2020-2-4

Hi,

I have a matrice R like :

R=zeros(3);

I need to change 3 array of R:

c=[1 1;3 2;1 2];

with new values in this vector:

Newvalue=[ 3 7 9];

So the final result is :

R=[3 9 0;0 0 0;0 7 0]

I know that I can do it easily with a For loop to check every element and replace new value.

But I want to vectorize this, i.e. with no loop.

KSSV 2020-2-4

编辑：KSSV 2020-2-4

Read about sub2ind.

R=zeros(3);
c=[1 1;3 2;1 2];
Newvalue=[ 3 7 9];
% get global indices 
idx = sub2ind(size(R),c(:,1),c(:,2)) ; 
R(idx) = Newvalue

amin 2020-2-4

Thank you so much, it is exacly what I was looking for.

MATLAB Language Fundamentals Data Types Numeric Types Logical

在 Help Center 和 File Exchange 中查找有关 Logical 的更多信息

Find the treasures in MATLAB Central and discover how the community can help you!

Translated by