why regexprep much slower than strrep

6 次查看（过去 30 天）
Oleg Komarov
Oleg Komarov 2014-11-16
Consider the following simplified example:
str = cellstr(repmat('987_890',1e5,1));
timeit(@()strrep(str,'_',''))
timeit(@()regexprep(str,'_',''))
strrep is ~3x faster than regexprep() on R014b - Win7 - cpu i5 3rd gen.
I reckon regexprep carries some overhead for being more flexible but I would expect it to be slightly slower than strrep unless it does the replacement on the go (to allow backtracking). However, in this simple substitution I hoped the engine was smart enough to recognize it does not need to backtrack.
Any thoughts?

请先登录，再回答此问题。

回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Just for fun 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