How can I search a cell array for all instances of a character and replace it with something else?

1 次查看（过去 30 天）
Andreea Juravschi
Andreea Juravschi 2019-10-29
回答： Rik 2019-10-29
Hi there!
I created a cell array that contains doubles with the occasional '*' as a space holder in some of the locations within the cell array itself. i need to find the astericks, and replace it with the average of the doubles above and below the astericks. I'm not sure how to go about searching for the astericks within a cell array?
Thank you!!

请先登录，再回答此问题。

回答（2 个）

Jos (10584)
Jos (10584) 2019-10-29
Something along these lines, perhaps?
C = {1.1 pi '*' ; 3 '*' 2.2}
tf = cellfun(@(x) isequal(x,'*'), C)
idx = find(tf)
Rik
Rik 2019-10-29
From your description, I suspect the simple fact that it is an asterisk doesn't actually matter. The code below will find all cell positions where there is a char and replace them by NaN. Then you have three options: loop through all indices you found, do some clever indexing, or replicate a shifted array. I went with the third (the first is easiest to implement boundary conditions, the second should scale best for large arrays, and the third is a bit of a middle ground).
clc
C = {1.1 pi '*' ; 3 '*' 2.2 ; 1 5 9};
tf = cellfun('isclass', C,'char');
C(tf)={NaN};
A=cell2mat(C)
[r,c]=find(tf);
A_row_shift_up= circshift(A,-1,1);
A_row_shift_up(end,:)=NaN;%blank out the bottom line
A_row_shift_down=circshift(A, 1,1);
A_row_shift_down(1,:)=NaN;%blank out the top line
A(tf)=mean(cat(3,A_row_shift_up(tf),A_row_shift_down(tf)),3,'omitnan')

类别

在 Help Center 和 File Exchange 中查找有关 Matrix Indexing 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