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Converting from positive flaot to negative float

Converting from positive flaot to negative float

Converting from positive flaot to negative float

Hello everybody

I've been tring to find a function or method for converting a posative float like -45.67 to a possative float (45.67). Using the NOT bitwise operator I can convert ints and using the abs function I can convert a negative float to a positive float but it won't work the other way.

I was thinking that I could take a possative number double it and then take that away from the original to get a negative number. E.G if i had the number 14.5 I could double it (29) and then take that from 14.5 and get -14.5 however I don't think this will work for numbers larger than half the maximum range of a float, as the doubling acion will give a number to large for the flaot to hold.

So my question is does any body have siggestions or information on how I might go about changing between posative and negative floats?

Thanks for you time

RE: Converting from positive flaot to negative float

For ints, doubles, or any other numeric type, just use operator-


#include <iostream>

int main()
    double d = -3.0;
    std::cout << d << '\n';
    d = -d;
    std::cout << d << '\n';
    d = -d;
    std::cout << d << '\n';

RE: Converting from positive flaot to negative float

lol...I knew there would be an easy solution. Thanks very much!

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