清空筛选条件
清空筛选条件

Replace values in one column based on the content in several other columns.

2 次查看（过去 30 天）
merialu
merialu 2018-11-13
评论： merialu 2018-11-14
Hi
I have two matrices containing x,y and z coordinates. These matrices also contain a column with values for each point.
Looks something like this:
A=[x y z value, 1 1 1 1; 1 2 1 0, 2 1 1 3, 2 1 2 4]
B=[x y z value, 1 1 1 1; 1 2 1 0]
the first matrix (A) have much more values than the second one (B). What i am trying to do is to replace the values in the large matrix (A) with the values from the smaller matrix (B) whenever the coordinates are the same. Thus the values in the x y and z column need to match.
Any ideas how to solve this?

请先登录，再回答此问题。

采纳的回答

Bruno Luong
Bruno Luong 2018-11-13
A = [1 1 1 0;
1 2 1 1;
2 1 1 3;
1 1 1 3;
2 1 2 4]
B = [1 1 1 1;
1 2 1 0]
[b,loc] = ismember(A(:,1:3),B(:,1:3),'rows');
A(b,:) = B(loc(b),:);
The result after replacement is
A =
1 1 1 1
1 2 1 0
2 1 1 3
1 1 1 1
2 1 2 4

更多回答（1 个）

madhan ravi
madhan ravi 2018-11-13
A=[ 1 1 1 1; 1 2 1 0; 2 1 1 3; 2 1 2 4] %perhaps?
B=[ 1 1 1 1; 1 2 1 0]
index=ismember(A(1:3,:),B,'rows')
A(index,:)=somevalues

类别

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

标签

Community Treasure Hunt

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

Start Hunting!

Translated by