I have a code writes a robot coordination in a file. Sometimes, for an unknown reason, instead of a number like 0.01845, it writes 6.92113e-310. So I'd like to filter data raised to a power greater than -12. Is there a way to achieve this in C++?
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3Yes, it's possible. If it's a number, you can compare with `1e-12`, e.g. `auto num = 6.92113e-310; if (num < 1e-12) ...` – jabaa Oct 25 '22 at 09:02
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1-310 is less than 12. It's even less than zero. `6.92113e-310.` is 0.0000(....)00069, there are 310 zeroes before the 6. – MSalters Oct 25 '22 at 14:13
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Round the output to a certain number of digits behind the decimal point. How do you output the data? cout? printf? fmt? – Sebastian Oct 25 '22 at 17:44
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@MSalters, sorry I made a mistake in question. It's not 12, but -12. – Edvard Oct 26 '22 at 06:55
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@Sebastian, I write data as myfile << parsed_data[0] << ";"; – Edvard Oct 26 '22 at 06:57
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@Edvard: Doesn't really change my point. -310 is also less than -12. – MSalters Oct 26 '22 at 09:42
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Just to help with the math: you get the exponent using std::log10.
This actually returns the exponent as the integer part, and the significand (the 6.9113 before the e) controls the fractional part of log10.
Filtering a collection by a predicate should be in your C++ textbook.
MSalters
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