			#define FUNC(x) ((*func)(x))

			double midpnt(double (*func)(double), double a, double b, int n)
			{
			double x,tnm,sum,del,ddel;
			static double s;
			int it,j;

			if (n == 1) {
			return (s=(b-a)FUNC(0.5(a+b)));
			} else {
			for(it=1,j=1;j<n-1;j++) it *= 3;
			tnm=it;
			del=(b-a)/(3.0*tnm);
			ddel=del+del;
			x=a+0.5*del;
			sum=0.0;
			for (j=1;j<=it;j++) {
			sum += FUNC(x);
			x += ddel;
			sum += FUNC(x);
			x += del;
			}
			s=(s+(b-a)*sum/tnm)/3.0;
			return s;
			}
			}
			#undef FUNC

R1448/ChiBenchmark/lenstoolchi/table_src/midpnt.c
c99f2e455a51lenstool-mixed

midpnt.c
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