square roots with C++
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how do i use them? i need them for a program i am making, but they aren't covered in the C++ book i have
i tried making it by using X^.5 but it just generates an error
Note that although X ^ 2 will compile, it is not a power operation.
^ is a bitwise XOR operation.
To use powers of, you can use pow() from <cmath>, or for simple powers just write it out longhand ( eg: for X cubed use (X * X * X) )
^ is a bitwise XOR operation.
To use powers of, you can use pow() from <cmath>, or for simple powers just write it out longhand ( eg: for X cubed use (X * X * X) )
Just a note... the sqrt and pow functions are extremely slow (as they do huge number of multiplications and divisions), so if you have to use them a lot (such as in a loop), try to avoid them if possible.
I'll have to disagree, marshdabeachy.
On current hardware, the sqrt and pow functions aren't that slow, and they certainly don't perform many arithmetic operations.
While these particular floating-point operations are relatively slow compared to integer arithmetic, they are lightning-fast compared to any alternative implementation (especially on SSE hardware and the likes). If you need to calculate a square root or calculate a power, you won't do any better than these functions unless you sacrifice a great deal of accuracy. Considering that you can reel off billions of sqrt()s per second, I really wouldn't worry about micro-optimisations like this.
Regards
Admiral
On current hardware, the sqrt and pow functions aren't that slow, and they certainly don't perform many arithmetic operations.
While these particular floating-point operations are relatively slow compared to integer arithmetic, they are lightning-fast compared to any alternative implementation (especially on SSE hardware and the likes). If you need to calculate a square root or calculate a power, you won't do any better than these functions unless you sacrifice a great deal of accuracy. Considering that you can reel off billions of sqrt()s per second, I really wouldn't worry about micro-optimisations like this.
Regards
Admiral
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