Is it possible to reduce this for loop into one line of code?

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Leon
Leon 2025-3-12
评论： Matt J 2025-3-13
My goal is to simplify the for-loop below to a one line of code. Please see attached for a mat file storing the Headers variable. Many thanks for any recommendations
% Find missing values in the Headers cell array:
Ind1 = cellfun(@(X)any(ismissing(X),'all'), Headers);
for i=1:numel(Ind1)
if Ind1(i)
Headers{i} = ['Missing_header_', num2str(i)];
end
end

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采纳的回答

Voss
Voss 2025-3-12
Ind1 = cellfun(@(X)any(ismissing(X),'all'), Headers);
Headers(Ind1) = cellstr("Missing_header_"+find(Ind1));

更多回答（3 个）

Walter Roberson
Walter Roberson 2025-3-12
Headers(cellfun(@(X)any(ismissing(X),'all'), Headers)) = cellstr("Missing_header_" + find(cellfun(@(X)any(ismissing(X),'all'), Headers)));
Just because you can do it on one line doesn't mean that you should do it on one line. I would recommend at least two lines
mask = cellfun(@(X)any(ismissing(X),'all'), Headers);
Headers(mask) = cellstr("Missing_header_" + find(mask));
Matt J
Matt J 2025-3-13
Headers = findMissing(Headers); %One line
  2 个评论
Matt J
Matt J 2025-3-13
Thanks, but I'm serious! All too often I see OP's forgetting that the whole point of user-defined functions is to reduce the number of lines of code.

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dpb
dpb 2025-3-12
编辑：dpb 2025-3-12
Ran in:
load test11
whos
Name Size Bytes Class Attributes Headers 1x6 826 cell ans 1x34 68 char
Headers
Headers = 1x6 cell array
{'Cruise ID'} {'Flag'} {'Missing_header_3'} {'Temp'} {'Missing_header_5'} {'EXPO'}
There aren't any missing in Headers so we'll make up some...
H=Headers;
H(3)={''}; H(5)=H(3)
H = 1x6 cell array
{'Cruise ID'} {'Flag'} {0x0 char} {'Temp'} {0x0 char} {'EXPO'}
H(ismissing(H))=compose('Missing_header_%d',find(ismissing(H)))
H = 1x6 cell array
{'Cruise ID'} {'Flag'} {'Missing_header_3'} {'Temp'} {'Missing_header_5'} {'EXPO'}
is one line of code albeit in order to do that one has to call ismissing twice't instead of using a temporary as did @Walter Roberson with whom I don't disagree that sometime just because can isn't necessarily any better than straightforward. Although I'd not use a loop here, I would probably choose the temporary since to satisfy the request the find is needed to get the positions...
ix=find(ismissing(H));
H(ix)=compose('Missing_header_%d',ix)
H = 1x6 cell array
{'Cruise ID'} {'Flag'} {'Missing_header_3'} {'Temp'} {'Missing_header_5'} {'EXPO'}
using compose to build an array of cellstrings instead of the new(ish) string class wherein numbers are silently converted to string representation and the plus operator is overloaded to concatenate strings that @Voss used.

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