*
* Implementation of Gamma function and some related stuff. */
+/*
+ * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
#include <vector>
#include <stdexcept>
-#include "ginac.h"
+#include "inifcns.h"
+#include "ex.h"
+#include "constant.h"
+#include "numeric.h"
+#include "power.h"
+#include "symbol.h"
//////////
// gamma function
numeric n = ex_to_numeric(x).sub(numHALF());
numeric coefficient = doublefactorial(n.mul(numTWO()).sub(numONE()));
coefficient = coefficient.div(numTWO().power(n));
- return mul(coefficient,power(Pi,numHALF()));
+ return coefficient * power(Pi,numHALF());
} else {
// trap negative x=(-n+1/2)
// gamma(-n+1/2) -> Pi^(1/2)*(-2)^n/(1*3*..*(2*n-1))
numeric n = abs(ex_to_numeric(x).sub(numHALF()));
numeric coefficient = numeric(-2).power(n);
coefficient = coefficient.div(doublefactorial(n.mul(numTWO()).sub(numONE())));;
- return mul(coefficient,power(Pi,numHALF()));
+ return coefficient * power(Pi,numHALF());
}
}
}