expr: renamed function log() to ln()

ChangeLog

@@ -5,6 +5,7 @@
 
 2016-03-17  Uwe Schulzweida
 
+	* expr: renamed function log() to ln()
 	* eca_cdd, eca_cwd: Added support to choose the amount of days
 
 2016-03-05  Uwe Schulzweida

doc/tex/mod/Exprf

@@ -65,7 +65,7 @@ Square of x
 Square Root of x
 @Item = exp(x)
 Exponential of x
-@Item = log(x)
+@Item = ln(x)
 Natural logarithm of x
 @Item = log10(x)
 Base 10 logarithm of x

src/expr.c

@@ -89,6 +89,7 @@ static func_t fun_sym_tbl[] =
   {FT_STD, 0, "exp",   (void (*)()) exp},
   {FT_STD, 0, "erf",   (void (*)()) erf},
   {FT_STD, 0, "log",   (void (*)()) log},
+  {FT_STD, 0, "ln",    (void (*)()) log},
   {FT_STD, 0, "log10", (void (*)()) log10},
   {FT_STD, 0, "sin",   (void (*)()) sin},
   {FT_STD, 0, "cos",   (void (*)()) cos},

src/operator_help.h

@@ -1353,7 +1353,7 @@ static const char *ExprHelp[] = {
     "    sqr(x)  "    "    Square of x",
     "    sqrt(x) "    "    Square Root of x",
     "    exp(x)  "    "    Exponential of x",
-    "    log(x)  "    "    Natural logarithm of x",
+    "    ln(x)   "    "    Natural logarithm of x",
     "    log10(x)"    "    Base 10 logarithm of x",
     "    sin(x)  "    "    Sine of x, where x is specified in radians",
     "    cos(x)  "    "    Cosine of x, where x is specified in radians",