[Rcpp-commits] r2195 - pkg/Rcpp/inst/examples/ConvolveBenchmarks

[noreply at r-forge.r-project.org]

Author: edd
Date: 2010-09-26 16:35:39 +0200 (Sun, 26 Sep 2010)
New Revision: 2195

Modified:
   pkg/Rcpp/inst/examples/ConvolveBenchmarks/convolve7_c.c
Log:
restore convolve7 to what it was


Modified: pkg/Rcpp/inst/examples/ConvolveBenchmarks/convolve7_c.c
===================================================================
--- pkg/Rcpp/inst/examples/ConvolveBenchmarks/convolve7_c.c	2010-09-26 14:01:27 UTC (rev 2194)
+++ pkg/Rcpp/inst/examples/ConvolveBenchmarks/convolve7_c.c	2010-09-26 14:35:39 UTC (rev 2195)
@@ -1,43 +1,28 @@
 
-/* This is from 'Writing R Extensions' section 5.10.1 */
+// This is from 'Writing R Extensions' section 5.10.1 
+// BUT slowed down by using REAL() on each access which proves to be rather costly
 
 #include <R.h>
 #include <Rdefines.h>
 
 SEXP convolve7(SEXP a, SEXP b)
 {
-    /* int i, j, na, nb, nab; */
-    /* SEXP ab; */
-
-    /* PROTECT(a = AS_NUMERIC(a)); */
-    /* PROTECT(b = AS_NUMERIC(b)); */
-    /* na = LENGTH(a); nb = LENGTH(b); nab = na + nb - 1; */
-    /* PROTECT(ab = NEW_NUMERIC(nab)); */
-    /* for(i = 0; i < nab; i++) REAL(ab)[i] = 0.0; */
-    /* for(i = 0; i < na; i++) */
-    /* 	for(j = 0; j < nb; j++) REAL(ab)[i + j] += REAL(a)[i] * REAL(b)[j]; */
-    /* UNPROTECT(3); */
-    /* return(ab); */
-
     int i, j, na, nb, nab;
-    double *xa, *xb, *xab;
     SEXP ab;
-    
+
     PROTECT(a = AS_NUMERIC(a));
     PROTECT(b = AS_NUMERIC(b));
     na = LENGTH(a); nb = LENGTH(b); nab = na + nb - 1;
     PROTECT(ab = NEW_NUMERIC(nab));
-    xa = NUMERIC_POINTER(a); xb = NUMERIC_POINTER(b);
-    xab = NUMERIC_POINTER(ab);
-    for(i = 0; i < nab; i++) xab[i] = 0.0;
+    for(i = 0; i < nab; i++) REAL(ab)[i] = 0.0;
     for(i = 0; i < na; i++)
-	for(j = 0; j < nb; j++) xab[i + j] += xa[i] * xb[j];
+    	for(j = 0; j < nb; j++) REAL(ab)[i + j] += REAL(a)[i] * REAL(b)[j];
     UNPROTECT(3);
     return(ab);
+
 }
 
 
-
 #include "loopmacro.h"
 LOOPMACRO_C(convolve7)