cmath isnan function

Wesley Smith wesley.hoke@gmail.com
Sun May 22 15:22:00 GMT 2005


I tried:

using namespace std;

before everything and it still failed to find isnan.

wes

On 5/22/05, Brian Budge <brian.budge@gmail.com> wrote:
> You need to be using the namespace std.
> 
> On 5/21/05, Wesley Smith <wesley.hoke@gmail.com> wrote:
> > Hi,
> >
> > I'm trying to compile a test program to see about the isnan function
> > on my system (apple darwin w/ gcc version 3.3 20030304 (Apple
> > Computer, Inc. build 1671).  Here's the code:
> >
> > #include <cmath>
> > int main()
> > {
> >  float x=sqrt(-1);
> >  return isnan(x);
> > }
> >
> > Here's the output:
> >
> > gcc -o main main.cpp
> > main.cpp: In function `int main()':
> > main.cpp:5: error: `isnan' undeclared (first use this function)
> > main.cpp:5: error: (Each undeclared identifier is reported only once for each
> >   function it appears in.)
> >
> > This is baffling since cmath is included and it redifines the macros
> > which it includes from math.h.  I completely stumped here and would
> > appreciate any help.
> >
> > thanks,
> > wes
> >
>



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