Make eval do evalf if arguments of gamma or beta are floats.

diff --git a/ginac/inifcns_gamma.cpp b/ginac/inifcns_gamma.cpp
index c9adc19967ad37a4da71f91b1929103a0cd58586..2770193f1ee018ed80d03b22dc0bb057707410ea 100644 (file)
--- a/ginac/inifcns_gamma.cpp
+++ b/ginac/inifcns_gamma.cpp
@@ -54,8 +54,7 @@ static ex lgamma_evalf(const ex & x)
 
 
 /** Evaluation of lgamma(x), the natural logarithm of the Gamma function.
- *  Knows about integer arguments and that's it.  Somebody ought to provide
- *  some good numerical evaluation some day...
+ *  Handles integer arguments as a special case.
  *
  *  @exception GiNaC::pole_error("lgamma_eval(): logarithmic pole",0) */
 static ex lgamma_eval(const ex & x)
@@ -69,7 +68,8 @@ static ex lgamma_eval(const ex & x)
                        else
                                throw (pole_error("lgamma_eval(): logarithmic pole",0));
                }
-               //  lgamma_evalf should be called here once it becomes available
+               if (!ex_to<numeric>(x).is_rational())
+                       return lgamma(ex_to<numeric>(x));
        }
        
        return lgamma(x).hold();
@@ -165,7 +165,8 @@ static ex tgamma_eval(const ex & x)
                                return (pow(*_num_2_p, n).div(doublefactorial(n.mul(*_num2_p).sub(*_num1_p))))*sqrt(Pi);
                        }
                }
-               //  tgamma_evalf should be called here once it becomes available
+               if (!ex_to<numeric>(x).is_rational())
+                       return tgamma(ex_to<numeric>(x));
        }
        
        return tgamma(x).hold();
@@ -262,7 +263,8 @@ static ex beta_eval(const ex & x, const ex & y)
                    (nx+ny).is_integer() &&
                   !(nx+ny).is_positive())
                         return _ex0;
-               // beta_evalf should be called here once it becomes available
+               if (!ex_to<numeric>(x).is_rational() || !ex_to<numeric>(x).is_rational())
+                       return evalf(beta(x, y).hold());
        }
        
        return beta(x,y).hold();