complex string match with regexprep

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S H 2019-5-14

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/462114-complex-string-match-with-regexprep

评论： Adam Danz 2019-5-14

What should be the expression in the following script to generate out from str?

str='diff([v0(k-1,2)-v0(k-1,1) v(2)-v(1)])/diff(t0(k-1:k))+((v(2)-0)*diff(t0(k-1:k))+sum((v0(2:k-1,2)-v0(2:k-1,10)).*diff(t0(1:k-1)).'',1))';
expression = ???;
replace = '0';
out=regexprep(str,expression,replace);
out='diff([v0(k-1,2)-v0(k-1,1) v(2)-v(1)])/diff(t0(k-1:k))+((v(2)-0)*diff(t0(k-1:k))+sum((v0(2:k-1,2)-0).*diff(t0(1:k-1)).'',1))'

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S H 2019-5-14

I tested your answer on my lengthy strings and it works as expected. Thank you for teaching me the use of [^,]* in regexprep. I was reading Matlab regexp help page a few times and such an important and helpful combination as [^,]* is not clearly explained there.

Adam Danz 2019-5-14

There are so many options with regular expressions that it's hard to capture them all in one document. I usually just google awkward phrases like "regular expressions match any character until" to remind myself of the options. The website I suggested in my answer is another great tool.

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采纳的回答

Adam Danz 2019-5-14

0
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此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/462114-complex-string-match-with-regexprep#answer_375033

编辑：Adam Danz 2019-5-14

在 MATLAB Online 中打开

Here you are.

str='diff([v0(k-1,2)-v0(k-1,1) v(2)-v(1)])/diff(t0(k-1:k))+((v(2)-0)*diff(t0(k-1:k))+sum((v0(2:k-1,2)-v0(2:k-1,10)).*diff(t0(1:k-1)).'',1))';
expression = 'v0\([^,]+,10\)'; 
replace = '0';
out = regexprep(str, expression, replace)

Compare input/output (I added space in output for comparison)

diff([v0(k-1,2)-v0(k-1,1) v(2)-v(1)])/diff(t0(k-1:k))+((v(2)-0)*diff(t0(k-1:k))+sum((v0(2:k-1,2)-v0(2:k-1,10)).*diff(t0(1:k-1)).',1))  %input
diff([v0(k-1,2)-v0(k-1,1) v(2)-v(1)])/diff(t0(k-1:k))+((v(2)-0)*diff(t0(k-1:k))+sum((v0(2:k-1,2)-0           ).*diff(t0(1:k-1)).',1))  %output