]> www.ginac.de Git - ginac.git/blobdiff - ginac/inifcns_gamma.cpp
Fixed initialization order bug (references to flyweights removed!) [C.Dams].
[ginac.git] / ginac / inifcns_gamma.cpp
index 6bf85621d8e6f8f216edcb182b44fa4b7d2ddeb0..baed308d366fba1a571e24989deca9f4c6c818a5 100644 (file)
@@ -4,7 +4,7 @@
  *  some related stuff. */
 
 /*
- *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2005 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
@@ -18,7 +18,7 @@
  *
  *  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
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
 #include <vector>
@@ -142,11 +142,11 @@ static ex tgamma_eval(const ex & x)
 {
        if (x.info(info_flags::numeric)) {
                // trap integer arguments:
-               const numeric two_x = _num2*ex_to<numeric>(x);
+               const numeric two_x = (*_num2_p)*ex_to<numeric>(x);
                if (two_x.is_even()) {
                        // tgamma(n) -> (n-1)! for postitive n
                        if (two_x.is_positive()) {
-                               return factorial(ex_to<numeric>(x).sub(_num1));
+                               return factorial(ex_to<numeric>(x).sub(*_num1_p));
                        } else {
                                throw (pole_error("tgamma_eval(): simple pole",1));
                        }
@@ -156,13 +156,13 @@ static ex tgamma_eval(const ex & x)
                        // trap positive x==(n+1/2)
                        // tgamma(n+1/2) -> Pi^(1/2)*(1*3*..*(2*n-1))/(2^n)
                        if (two_x.is_positive()) {
-                               const numeric n = ex_to<numeric>(x).sub(_num1_2);
-                               return (doublefactorial(n.mul(_num2).sub(_num1)).div(pow(_num2,n))) * sqrt(Pi);
+                               const numeric n = ex_to<numeric>(x).sub(*_num1_2_p);
+                               return (doublefactorial(n.mul(*_num2_p).sub(*_num1_p)).div(pow(*_num2_p,n))) * sqrt(Pi);
                        } else {
                                // trap negative x==(-n+1/2)
                                // tgamma(-n+1/2) -> Pi^(1/2)*(-2)^n/(1*3*..*(2*n-1))
-                               const numeric n = abs(ex_to<numeric>(x).sub(_num1_2));
-                               return (pow(_num_2, n).div(doublefactorial(n.mul(_num2).sub(_num1))))*sqrt(Pi);
+                               const numeric n = abs(ex_to<numeric>(x).sub(*_num1_2_p));
+                               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
@@ -193,7 +193,7 @@ static ex tgamma_series(const ex & arg,
        //   tgamma(x) == tgamma(x+1) / x
        // from which follows
        //   series(tgamma(x),x==-m,order) ==
-       //   series(tgamma(x+m+1)/(x*(x+1)*...*(x+m)),x==-m,order+1);
+       //   series(tgamma(x+m+1)/(x*(x+1)*...*(x+m)),x==-m,order);
        const ex arg_pt = arg.subs(rel, subs_options::no_pattern);
        if (!arg_pt.info(info_flags::integer) || arg_pt.info(info_flags::positive))
                throw do_taylor();  // caught by function::series()
@@ -202,7 +202,7 @@ static ex tgamma_series(const ex & arg,
        ex ser_denom = _ex1;
        for (numeric p; p<=m; ++p)
                ser_denom *= arg+p;
-       return (tgamma(arg+m+_ex1)/ser_denom).series(rel, order+1, options);
+       return (tgamma(arg+m+_ex1)/ser_denom).series(rel, order, options);
 }
 
 
@@ -245,13 +245,13 @@ static ex beta_eval(const ex & x, const ex & y)
                        ny.is_real() && ny.is_integer()) {
                        if (nx.is_negative()) {
                                if (nx<=-ny)
-                                       return pow(_num_1, ny)*beta(1-x-y, y);
+                                       return pow(*_num_1_p, ny)*beta(1-x-y, y);
                                else
                                        throw (pole_error("beta_eval(): simple pole",1));
                        }
                        if (ny.is_negative()) {
                                if (ny<=-nx)
-                                       return pow(_num_1, nx)*beta(1-y-x, x);
+                                       return pow(*_num_1_p, nx)*beta(1-y-x, x);
                                else
                                        throw (pole_error("beta_eval(): simple pole",1));
                        }
@@ -304,19 +304,19 @@ static ex beta_series(const ex & arg1,
                throw do_taylor();  // caught by function::series()
        // trap the case where arg1 is on a pole:
        if (arg1.info(info_flags::integer) && !arg1.info(info_flags::positive))
-               arg1_ser = tgamma(arg1+s).series(rel, order, options);
+               arg1_ser = tgamma(arg1+s);
        else
-               arg1_ser = tgamma(arg1).series(rel,order);
+               arg1_ser = tgamma(arg1);
        // trap the case where arg2 is on a pole:
        if (arg2.info(info_flags::integer) && !arg2.info(info_flags::positive))
-               arg2_ser = tgamma(arg2+s).series(rel, order, options);
+               arg2_ser = tgamma(arg2+s);
        else
-               arg2_ser = tgamma(arg2).series(rel,order);
+               arg2_ser = tgamma(arg2);
        // trap the case where arg1+arg2 is on a pole:
        if ((arg1+arg2).info(info_flags::integer) && !(arg1+arg2).info(info_flags::positive))
-               arg1arg2_ser = tgamma(arg2+arg1+s).series(rel, order, options);
+               arg1arg2_ser = tgamma(arg2+arg1+s);
        else
-               arg1arg2_ser = tgamma(arg2+arg1).series(rel,order);
+               arg1arg2_ser = tgamma(arg2+arg1);
        // compose the result (expanding all the terms):
        return (arg1_ser*arg2_ser/arg1arg2_ser).series(rel, order, options).expand();
 }
@@ -356,7 +356,7 @@ static ex psi1_eval(const ex & x)
                        if (nx.is_positive()) {
                                // psi(n) -> 1 + 1/2 +...+ 1/(n-1) - Euler
                                numeric rat = 0;
-                               for (numeric i(nx+_num_1); i>0; --i)
+                               for (numeric i(nx+(*_num_1_p)); i>0; --i)
                                        rat += i.inverse();
                                return rat-Euler;
                        } else {
@@ -364,13 +364,13 @@ static ex psi1_eval(const ex & x)
                                throw (pole_error("psi_eval(): simple pole",1));
                        }
                }
-               if ((_num2*nx).is_integer()) {
+               if (((*_num2_p)*nx).is_integer()) {
                        // half integer case
                        if (nx.is_positive()) {
                                // psi((2m+1)/2) -> 2/(2m+1) + 2/2m +...+ 2/1 - Euler - 2log(2)
                                numeric rat = 0;
-                               for (numeric i = (nx+_num_1)*_num2; i>0; i-=_num2)
-                                       rat += _num2*i.inverse();
+                               for (numeric i = (nx+(*_num_1_p))*(*_num2_p); i>0; i-=(*_num2_p))
+                                       rat += (*_num2_p)*i.inverse();
                                return rat-Euler-_ex2*log(_ex2);
                        } else {
                                // use the recurrence relation
@@ -380,7 +380,7 @@ static ex psi1_eval(const ex & x)
                                // where r == ((-1/2)^(-1) + ... + (-m-1/2)^(-1))
                                numeric recur = 0;
                                for (numeric p = nx; p<0; ++p)
-                                       recur -= pow(p, _num_1);
+                                       recur -= pow(p, *_num_1_p);
                                return recur+psi(_ex1_2);
                        }
                }
@@ -423,7 +423,7 @@ static ex psi1_series(const ex & arg,
 }
 
 unsigned psi1_SERIAL::serial =
-       function::register_new(function_options("psi").
+       function::register_new(function_options("psi", 1).
                               eval_func(psi1_eval).
                               evalf_func(psi1_evalf).
                               derivative_func(psi1_deriv).
@@ -462,9 +462,9 @@ static ex psi2_eval(const ex & n, const ex & x)
                const numeric &nx = ex_to<numeric>(x);
                if (nx.is_integer()) {
                        // integer case 
-                       if (nx.is_equal(_num1))
+                       if (nx.is_equal(*_num1_p))
                                // use psi(n,1) == (-)^(n+1) * n! * zeta(n+1)
-                               return pow(_num_1,nn+_num1)*factorial(nn)*zeta(ex(nn+_num1));
+                               return pow(*_num_1_p,nn+(*_num1_p))*factorial(nn)*zeta(ex(nn+(*_num1_p)));
                        if (nx.is_positive()) {
                                // use the recurrence relation
                                //   psi(n,m) == psi(n,m+1) - (-)^n * n! / m^(n+1)
@@ -473,25 +473,25 @@ static ex psi2_eval(const ex & n, const ex & x)
                                // where r == (-)^n * n! * (1^(-n-1) + ... + (m-1)^(-n-1))
                                numeric recur = 0;
                                for (numeric p = 1; p<nx; ++p)
-                                       recur += pow(p, -nn+_num_1);
-                               recur *= factorial(nn)*pow(_num_1, nn);
+                                       recur += pow(p, -nn+(*_num_1_p));
+                               recur *= factorial(nn)*pow((*_num_1_p), nn);
                                return recur+psi(n,_ex1);
                        } else {
                                // for non-positive integers there is a pole:
                                throw (pole_error("psi2_eval(): pole",1));
                        }
                }
-               if ((_num2*nx).is_integer()) {
+               if (((*_num2_p)*nx).is_integer()) {
                        // half integer case
-                       if (nx.is_equal(_num1_2))
+                       if (nx.is_equal(*_num1_2_p))
                                // use psi(n,1/2) == (-)^(n+1) * n! * (2^(n+1)-1) * zeta(n+1)
-                               return pow(_num_1,nn+_num1)*factorial(nn)*(pow(_num2,nn+_num1) + _num_1)*zeta(ex(nn+_num1));
+                               return pow(*_num_1_p,nn+(*_num1_p))*factorial(nn)*(pow(*_num2_p,nn+(*_num1_p)) + (*_num_1_p))*zeta(ex(nn+(*_num1_p)));
                        if (nx.is_positive()) {
-                               const numeric m = nx - _num1_2;
+                               const numeric m = nx - (*_num1_2_p);
                                // use the multiplication formula
                                //   psi(n,2*m) == (psi(n,m) + psi(n,m+1/2)) / 2^(n+1)
                                // to revert to positive integer case
-                               return psi(n,_num2*m)*pow(_num2,nn+_num1)-psi(n,m);
+                               return psi(n,(*_num2_p)*m)*pow((*_num2_p),nn+(*_num1_p))-psi(n,m);
                        } else {
                                // use the recurrence relation
                                //   psi(n,-m-1/2) == psi(n,-m-1/2+1) - (-)^n * n! / (-m-1/2)^(n+1)
@@ -500,8 +500,8 @@ static ex psi2_eval(const ex & n, const ex & x)
                                // where r == (-)^(n+1) * n! * ((-1/2)^(-n-1) + ... + (-m-1/2)^(-n-1))
                                numeric recur = 0;
                                for (numeric p = nx; p<0; ++p)
-                                       recur += pow(p, -nn+_num_1);
-                               recur *= factorial(nn)*pow(_num_1, nn+_num_1);
+                                       recur += pow(p, -nn+(*_num_1_p));
+                               recur *= factorial(nn)*pow(*_num_1_p, nn+(*_num_1_p));
                                return recur+psi(n,_ex1_2);
                        }
                }
@@ -551,7 +551,7 @@ static ex psi2_series(const ex & n,
 }
 
 unsigned psi2_SERIAL::serial =
-       function::register_new(function_options("psi").
+       function::register_new(function_options("psi", 2).
                               eval_func(psi2_eval).
                               evalf_func(psi2_evalf).
                               derivative_func(psi2_deriv).