fmod doesnt recognize zeros

I have a big loop using double numbers, and Im using fmod to print "*" when I have modulo equals zero:

for(double tp=0 ; tp<=1 ; tp=tp+0.01) {
    for(double p=0  ; p<=1 ; p=p+0.01) {
        tt=1+2*tp;
        for(double t=0 ; t<1000 ; t+=0.01) {
            printf(" t=%f (tt=%f) (%%=%f)|",t,tt,fmod(t,tt));
            if(fmod(t,tt)==0.0) {
                printf("*");
            }
        }
}

when I run this, I can see a lot of zeros in " (%%=%f) " - which prints the result of the fmod. but I cant find "*" !! menas the if statment returns false even the result euqals zero!!! why is that? thanks alot