如何設定矩陣中特定元素的值

[m1,m2]=find(www=='Ref');
f=zeros(480,640);
f(m1,m2)=1;

m1、m2分別為一個n*1的矩陣，若我想把f矩陣中每個對應的(m1,m2)元素設為1，

例如:m1=[1,2,3]，m2=[4,5,6]，而我想設定f(1,4)、f(2,5)及f(3,6)都等於1，

請問我該怎麼編寫代碼，謝謝。

Answer 1

[Gagan Agarwal]

Hi Dun-Ren Liu

To accomplish your desired objective, you have the option to utilize the built-in “sub2ind” function available in MATLAB. Please refer to the sample code provided as an example.

f = zeros(5,5);
x = [1,2,3]';
y = [1,2,3]';
idx = sub2ind(size(f),x,y);
f(idx) = 1; 

In this code snippet, “f” represents the matrix whose values you intend to modify, while “x” and “y” are vectors that store the row and column indices, respectively.