[Commit-gnuradio] r8324 - in gnuradio/trunk: . gnuradio-core/src/lib/viterbi

[eb]

Author: eb
Date: 2008-05-08 00:17:55 -0600 (Thu, 08 May 2008)
New Revision: 8324

Modified:
   gnuradio/trunk/configure.ac
   gnuradio/trunk/gnuradio-core/src/lib/viterbi/metrics.c
Log:
better fix for ticket:243

Modified: gnuradio/trunk/configure.ac
===================================================================
--- gnuradio/trunk/configure.ac 2008-05-08 05:41:23 UTC (rev 8323)
+++ gnuradio/trunk/configure.ac 2008-05-08 06:17:55 UTC (rev 8324)
@@ -152,6 +152,7 @@
 AC_CHECK_LIB(m, cosf, [AC_DEFINE([HAVE_COSF],[1],[Define to 1 if your system 
has `cosf'.])])
 AC_CHECK_LIB(m, trunc, [AC_DEFINE([HAVE_TRUNC],[1],[Define to 1 if your system 
has `trunc'.])])
 AC_CHECK_LIB(m, exp10, [AC_DEFINE([HAVE_EXP10],[1],[Define to 1 if your system 
has 'exp10'.])])
+AC_CHECK_LIB(m, log2, [AC_DEFINE([HAVE_LOG2],[1],[Define to 1 if your system 
has 'log2'.])])
 #AC_FUNC_MKTIME
 
 AH_BOTTOM([

Modified: gnuradio/trunk/gnuradio-core/src/lib/viterbi/metrics.c
===================================================================
--- gnuradio/trunk/gnuradio-core/src/lib/viterbi/metrics.c      2008-05-08 
05:41:23 UTC (rev 8323)
+++ gnuradio/trunk/gnuradio-core/src/lib/viterbi/metrics.c      2008-05-08 
06:17:55 UTC (rev 8324)
@@ -30,6 +30,10 @@
  *
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 /* Symbols are offset-binary, with 128 corresponding to an erased (no
  * information) symbol
  */
@@ -41,6 +45,12 @@
 /* Normal function integrated from -Inf to x. Range: 0-1 */
 #define        normal(x)       (0.5 + 0.5*erf((x)/M_SQRT2))
 
+/* Logarithm base 2 */ 
+double log2(double);           /* declaration seems to be missing from some 
math.h's */
+#if !defined(HAVE_LOG2)
+#define log2(x) (log(x)*M_LOG2E)
+#endif
+
 /* Generate log-likelihood metrics for 8-bit soft quantized channel
  * assuming AWGN and BPSK
  */