You need to be using the namespace std.
On 5/21/05, Wesley Smith <wesley.hoke@xxxxxxxxx> 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
>
