I have a string and I need to evaluate its numerical value, e.g. a='5.1+2.3-1.9'
I tried using type conversion but it's not working. Error "Could not convert string to float".
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wjandrea
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Sreyans Gupta
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You can use eval, but this means that it will evaluate everything what you put in there, even: __import__('os').system('rm -rf /a-path-you-really-care-about') (source).
A better solution was provided in this stackoverflow (SO) post and advises you to use something like numexpr, which are a lot safer.
Thymen
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eval returns int value..expected output is float. – Sreyans Gupta Nov 29 '20 at 20:53
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@Sreyans `eval('5.1+2.3-1.9')` returns 5.5 for me. What version of Python are you using, and what are you running exactly? – wjandrea Nov 29 '20 at 21:15
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@Sreyans I get the same results as @wjandrea, which is `5.5` for the example that you posted. – Thymen Nov 29 '20 at 21:52