[Dplr-commits] r711 - in pkg/dplR: . R

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

Author: mvkorpel
Date: 2013-10-29 15:36:18 +0100 (Tue, 29 Oct 2013)
New Revision: 711

Modified:
   pkg/dplR/ChangeLog
   pkg/dplR/R/redfit.R
Log:
redfit.R: Precomputed squared numbers in getdof()

Modified: pkg/dplR/ChangeLog
===================================================================
--- pkg/dplR/ChangeLog	2013-10-29 14:19:46 UTC (rev 710)
+++ pkg/dplR/ChangeLog	2013-10-29 14:36:18 UTC (rev 711)
@@ -5,6 +5,7 @@
 
 - Use slightly faster .rowSums() instead of rowSums()
 - Simplified arithmetic expressions in getdof(): no multiplying by 2
+- Precomputed squared numbers in getdof()
 
 * CHANGES IN dplR VERSION 1.5.7
 

Modified: pkg/dplR/R/redfit.R
===================================================================
--- pkg/dplR/R/redfit.R	2013-10-29 14:19:46 UTC (rev 710)
+++ pkg/dplR/R/redfit.R	2013-10-29 14:36:18 UTC (rev 711)
@@ -550,8 +550,11 @@
     ## dplR: Computed more precise values for c50.
     getdof <- function(iwin, n50) {
         ## dplR: Rectangular, Welch, Hanning, Triangular, Blackman-Harris
-        c50 <- c(0.5, 0.34375, 1 / 6, 0.25, 0.0955489871755)
-        c2 <- c50[iwin + 1]^2
+        ## c50 <- c(0.5, 0.34375, 1 / 6, 0.25, 0.0955489871755)
+        ## c2 <- c50[iwin + 1]^2
+        ## dplR: Precomputed squared c50. Note: (1/6)^2 == 1/36
+        c2 <- c(0.25, 0.1181640625, 0.0277777777777778,
+                0.0625, 0.00912960895026386)[iwin + 1]
         n50 / (0.5 + c2 - c2 / n50)
     }
     ## dplR: Automatically adds prefix (for example "# " from REDFIT) and