X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Finifcns_gamma.cpp;h=46c8ea9e00e717652b188a0979f18224bc639fa0;hp=0fabbca7157a7bfc5363a203ebbdd4a3fc7fd362;hb=94ead6345f31939c9c9eff70ce88d74cf36a8004;hpb=67edef78ce992a8f6ad704bfac228b8dec6eacd2

diff --git a/ginac/inifcns_gamma.cpp b/ginac/inifcns_gamma.cpp
index 0fabbca7..46c8ea9e 100644
--- a/ginac/inifcns_gamma.cpp
+++ b/ginac/inifcns_gamma.cpp
@@ -110,10 +110,26 @@ static ex lgamma_series(const ex & arg,
 }
 
 
+static ex lgamma_conjugate(const ex & x)
+{
+	// conjugate(lgamma(x))==lgamma(conjugate(x)) unless on the branch cut
+	// which runs along the negative real axis.
+	if (x.info(info_flags::positive)) {
+		return lgamma(x);
+	}
+	if (is_exactly_a<numeric>(x) &&
+	    !x.imag_part().is_zero()) {
+		return lgamma(x.conjugate());
+	}
+	return conjugate_function(lgamma(x)).hold();
+}
+
+
 REGISTER_FUNCTION(lgamma, eval_func(lgamma_eval).
                           evalf_func(lgamma_evalf).
                           derivative_func(lgamma_deriv).
                           series_func(lgamma_series).
+                          conjugate_func(lgamma_conjugate).
                           latex_name("\\log \\Gamma"));
 
 
@@ -207,10 +223,18 @@ static ex tgamma_series(const ex & arg,
 }
 
 
+static ex tgamma_conjugate(const ex & x)
+{
+	// conjugate(tgamma(x))==tgamma(conjugate(x))
+	return tgamma(x.conjugate());
+}
+
+
 REGISTER_FUNCTION(tgamma, eval_func(tgamma_eval).
                           evalf_func(tgamma_evalf).
                           derivative_func(tgamma_deriv).
                           series_func(tgamma_series).
+                          conjugate_func(tgamma_conjugate).
                           latex_name("\\Gamma"));
 
 
@@ -329,7 +353,7 @@ REGISTER_FUNCTION(beta, eval_func(beta_eval).
                         derivative_func(beta_deriv).
                         series_func(beta_series).
                         latex_name("\\mathrm{B}").
-						set_symmetry(sy_symm(0, 1)));
+                        set_symmetry(sy_symm(0, 1)));
 
 
 //////////