Re: is it ok to cast variables? simple function using std::pow
"aaragon" <alejandro.aragon@gmail.com> wrote in message
news:1181181519.657669.250120@q69g2000hsb.googlegroups.com...
Hi everyone,
I wrote a very simple function to try to understand the casting of
variables in C++. The function is
function foo()
{
std::vector<int> test(100);
randomize(test);
unsigned long x = 0;
for(int i=0; i<test.size(); i++)
x += (unsigned long)(allele(i)*std::pow((double)k,
(double)i));
}
The function randomize just creates random values inside the vector.
This was the only way I made it to work without having any warnings
from the compiler. Since the std::pow takes two doubles as parameters,
I needed to cast the integer values into doubles. Also, I needed to
cast those double results into an unsigned long integer. I don't
really like using casting (I have a bad feeling every time I use it)
but I couldn't find a better way to do this. Does anyone have a better
way to do it? Is there anything wrong with casting variables into
different types?
Bascially, that's how I also use pow with intergers, although I use
static_cast rather than a c-style cast as it's explicit what I'm doing. (
static_cast<double>k, static_cast<double>i )
I put a static_cast in when I get a warning and I know that what I'm doing
is what I want to do and I either won't be getting over/underflow or I'm
handling it myself somewhere.
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