Assign vector to vector with gaps

Question

baxbear 2016-7-16

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/296015-assign-vector-to-vector-with-gaps

评论： baxbear 2016-7-22

采纳的回答： goerk

在 MATLAB Online 中打开

Stuff doesn't matter - was tired - start reading at Edit1 - sry

Hello,

I have a matrix of row size m and a matrix of row size n where m > n and x = m - n. I also got a vector k of length x with different row indices of m. Now I want to assign n to m by not touching entries m(k) important is that these rows stay unchanged and in place.

Is there an easy one-liner? like:

m(m ~= x) = n;

or

m(m ~= m(x)) = n;

but seems not to work :(

Hope you can help me.

Thanks in advance.

=================================================================

HERE!:-> @Edit1: Oh, uff was late yesterday and yeah what ever I wrote there is pretty confusing and wrong... so again:

Matrix A of size m * _ where m is the number of rows and matrix B of size n * _ where n is the number of rows. Still true is: m > n and x = m - n and V is a vector with x rows.

Example:

A = [1,1,1; 2,2,1; 3,3,4; 8,3,6; 8,3,0; 8,6,3];
B = [4,2,5; 4,3,2; 6,3,2; 8,0,9];
V = [2; 4];

Result in A:

A = [4,2,5; 2,2,1; 4,3,2; 8,3,6; 6,3,2; 8,0,9];

just for much bigger matrices. Sorry for my unclear post yesterday hope you are still willing to help me.

2 个评论
显示无隐藏无

Azzi Abdelmalek 2016-7-16

You can make your question clear by posting an example

Image Analyst 2016-7-16

编辑：Image Analyst 2016-7-16

在 MATLAB Online 中打开

Your terminology is pretty sloppy. Are m and n the width of the matrix (number of columns which is the "row size" or "row length") or the names of the matrices? Are your matrices really column vectors? Or row vectors?

This is what I have so far but can't go further because of ambiguities in your terminology.

m=10
n=6
x = m-n
vec1 = randi(99, 1, m) % First "matrix" (sample data)
vec2 = randi(99, 1, n) % Second "matrix" (sample data)
k = randperm(m, x) % indexes of m

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

goerk 2016-7-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/296015-assign-vector-to-vector-with-gaps#answer_229110

在 MATLAB Online 中打开

 A = [1,1,1; 2,2,1; 3,3,4; 8,3,6; 8,3,0; 8,6,3];
 B = [4,2,5; 4,3,2; 6,3,2; 8,0,9];
 V = [2; 4];
 % create 'inversion' of V (there may be better ways) 
 notV = 1:size(A,1);  % vector from 1 to number of rows
 notV(V) = [];  % delete rows which are in V
 % over write the rows that are not in V
 A(notV,:)=B