Select last numeric character(s) of the string
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Hello,
I'm hoping for an advise on the code which has to do with extracting the digits (either 1,2 or 3) from the string which includes different condition names. It's about a rating from -100 to 100 given to different conditions.
In our other script the output gave the ratings saves as: e.g "sucrose: 10". Now it's: e.g. "sucrose10".
How can I extract the last numbers occurring at the end of different strings? I'll provide the code we had below to deal with the separation using ":" which now doesn't work.
log.rating = zeros(height(log),1);
for l = 1:height(log)
if contains(char(log.Code(l)),'score','IgnoreCase',true)
scorestring = char(log.Code(l));
if strcmp(scorestring(end-3:end),'-100')
log.rating(l) = str2double(str(scorestring(end-3:end)));
elseif ~contains(scorestring(end-2:end))
log.rating(l) = str2double(str(scorestring(end-2:end)));
else
log.rating(l) = str2double(str(scorestring(end-1:end)));
end
else
log.rating(l) = NaN;
end
end
Many thanks!!
采纳的回答
"How can I extract the last numbers occurring at the end of different strings?"
X = "sucrose-10";
Y = str2double(regexp(X,'[-+]?\d{1,3}$','match','once'))
This replaces your innermost IF-ELSEIF-ELSE-END. You could probably use it to replace you entire FOR loop too.
It detects from 1 to 3 digits at the end of the text.
It will also detect an optional +/- sign in front of those digits.
See also:
2 个评论
Assuming that LOG is a table (you did not explain this in your question):
log = array2table(["scoreABC-23";"DEF 100";"scoreGHI-100";"JKLscore: 99"], 'VariableNames',{'Code'})
idx = contains(log.Code,'score','IgnoreCase',true);
log.Rating = nan(size(log.Code));
log.Rating(idx) = str2double(regexp(log.Code(idx),'[-+]?\d{1,3}$','match','once'))
Don't fight MATLAB with loops and IFs. Think in terms of vectors and matrices.
Aleksandra Budzinska
2023-4-25
更多回答（1 个）
output = 'sucrose: 10';
numbers = str2double(extract(output, digitsPattern))
output = "sucrose10";
numbers = str2double(extract(output, digitsPattern))
2 个评论
Aleksandra Budzinska
2023-4-25
"although I don't understand the difference between your first and second code. "
@Aleksandra Budzinska, they are the same code, Kevin just used two different inputs to show the result.
output = 'Sucrose high-100';
numbers = str2double(extract(output, digitsPattern))
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