MATLAB Answers

How do I add a value to a field in each element of a struct array?

조회 수: 117(최근 30일)
Brandon Kuczenski
Brandon Kuczenski 29 Apr 2014
댓글: Image Analyst 29 Apr 2014
Say I have a struct array with a numeric field:
>> a=struct('bar',{47 52})
I want to increment that field across each element of the array, something like the following:
>> [] = [] + 1; % this fails
The nearest I can figure out is the following, which is cumbersome:
>> inc = num2cell([]+1);
>> [] = inc{:};
Is there a way to do this without creating an intermediate variable? Thanks in advance.


Image Analyst
Image Analyst 29 Apr 2014
Well why are you messing around with cell arrays? Why make it way more complicated than it needs to be??? I don't see any reason for a cell array. I think you need to read the FAQ:
Try using just regular numerical arrays:
% Create structure.
a=struct('bar',[47 52]) % Report to command window.
% Add 1 = % Report to command window.
In the command window:
a =
bar: [47 52]
ans =
47 52
a =
bar: [48 53]
ans =
48 53
  댓글 수: 2
Image Analyst
Image Analyst 29 Apr 2014
Sorry, I misunderstood. A fast, straightforward and intuitive solution is to simply use a for loop:
for k = 1:length(a)
a(k).bar = a(k).bar+1;
Don't believe the hype about a for loop being slow. It's not. Assuming you have less than several million structures in the array, it should be very fast.

댓글을 달려면 로그인하십시오.


Community Treasure Hunt

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

Start Hunting!

Translated by