Fractional powers!

1 files changed, 6 insertions, 1 deletions

diff --git a/attract.c b/attract.c
index bd7717d..16f1703 100644
--- a/attract.c
+++ b/attract.c
@@ -16,6 +16,7 @@ const int MAXITER=200;
 const double EPS=1e-1;
 
 static double complex att_func(double complex x){
+#if 0
 	static const int N=9;
 
 	double complex r=1,y=x;
@@ -25,6 +26,10 @@ static double complex att_func(double complex x){
 	}
 	r+=y;
 	return clog(r);
+#else
+	static const double N=8.5;
+	return clog((1-cpow(x,N+1))/(1-x));
+#endif
 }
 
 struct colour{
@@ -123,7 +128,7 @@ int main(void){
 	unsigned char img[cfg.width*cfg.height*3];
 
 	int nthreads=sysconf(_SC_NPROCESSORS_ONLN);
-	nthreads/=2;
+	if(nthreads==4)nthreads/=2;
 	if(nthreads>=999||nthreads<1)nthreads=1;
 	fprintf(stderr,"Using %d thread%s\n",nthreads,nthreads==1?"":"s");