Improved series expansion synced to HEAD.

[ginac.git] / ginac / inifcns_trans.cpp

diff --git a/ginac/inifcns_trans.cpp b/ginac/inifcns_trans.cpp
index 79d7cd473de2c0dcc0f07190a709d8feab9535b4..c12df144c8bcedeb534318f57bba695b2a053520 100644 (file)
--- a/ginac/inifcns_trans.cpp
+++ b/ginac/inifcns_trans.cpp
@@ -4,7 +4,7 @@
  *  functions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2003 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2004 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
@@ -124,6 +124,9 @@ static ex log_eval(const ex & x)
        // log(exp(t)) -> t (if -Pi < t.imag() <= Pi):
        if (is_ex_the_function(x, exp)) {
                const ex &t = x.op(0);
+               if (is_a<symbol>(t) && t.info(info_flags::real)) {
+                       return t;
+               }
                if (t.info(info_flags::numeric)) {
                        const numeric &nt = ex_to<numeric>(t);
                        if (nt.is_real())
@@ -152,7 +155,7 @@ static ex log_series(const ex &arg,
        bool must_expand_arg = false;
        // maybe substitution of rel into arg fails because of a pole
        try {
-               arg_pt = arg.subs(rel);
+               arg_pt = arg.subs(rel, subs_options::no_pattern);
        } catch (pole_error) {
                must_expand_arg = true;
        }
@@ -206,7 +209,7 @@ static ex log_series(const ex &arg,
                const symbol &s = ex_to<symbol>(rel.lhs());
                const ex &point = rel.rhs();
                const symbol foo;
-               const ex replarg = series(log(arg), s==foo, order).subs(foo==point);
+               const ex replarg = series(log(arg), s==foo, order).subs(foo==point, subs_options::no_pattern);
                epvector seq;
                seq.push_back(expair(-I*csgn(arg*I)*Pi, _ex0));
                seq.push_back(expair(Order(_ex1), order));
@@ -465,11 +468,11 @@ static ex tan_series(const ex &x,
        // method:
        // Taylor series where there is no pole falls back to tan_deriv.
        // On a pole simply expand sin(x)/cos(x).
-       const ex x_pt = x.subs(rel);
+       const ex x_pt = x.subs(rel, subs_options::no_pattern);
        if (!(2*x_pt/Pi).info(info_flags::odd))
                throw do_taylor();  // caught by function::series()
        // if we got here we have to care for a simple pole
-       return (sin(x)/cos(x)).series(rel, order+2, options);
+       return (sin(x)/cos(x)).series(rel, order, options);
 }
 
 REGISTER_FUNCTION(tan, eval_func(tan_eval).
@@ -636,7 +639,7 @@ static ex atan_series(const ex &arg,
        // On the branch cuts and the poles series expand
        //     (log(1+I*x)-log(1-I*x))/(2*I)
        // instead.
-       const ex arg_pt = arg.subs(rel);
+       const ex arg_pt = arg.subs(rel, subs_options::no_pattern);
        if (!(I*arg_pt).info(info_flags::real))
                throw do_taylor();     // Re(x) != 0
        if ((I*arg_pt).info(info_flags::real) && abs(I*arg_pt)<_ex1)
@@ -651,7 +654,7 @@ static ex atan_series(const ex &arg,
                const symbol &s = ex_to<symbol>(rel.lhs());
                const ex &point = rel.rhs();
                const symbol foo;
-               const ex replarg = series(atan(arg), s==foo, order).subs(foo==point);
+               const ex replarg = series(atan(arg), s==foo, order).subs(foo==point, subs_options::no_pattern);
                ex Order0correction = replarg.op(0)+csgn(arg)*Pi*_ex_1_2;
                if ((I*arg_pt)<_ex0)
                        Order0correction += log((I*arg_pt+_ex_1)/(I*arg_pt+_ex1))*I*_ex_1_2;
@@ -875,11 +878,11 @@ static ex tanh_series(const ex &x,
        // method:
        // Taylor series where there is no pole falls back to tanh_deriv.
        // On a pole simply expand sinh(x)/cosh(x).
-       const ex x_pt = x.subs(rel);
+       const ex x_pt = x.subs(rel, subs_options::no_pattern);
        if (!(2*I*x_pt/Pi).info(info_flags::odd))
                throw do_taylor();  // caught by function::series()
        // if we got here we have to care for a simple pole
-       return (sinh(x)/cosh(x)).series(rel, order+2, options);
+       return (sinh(x)/cosh(x)).series(rel, order, options);
 }
 
 REGISTER_FUNCTION(tanh, eval_func(tanh_eval).
@@ -1020,7 +1023,7 @@ static ex atanh_series(const ex &arg,
        // On the branch cuts and the poles series expand
        //     (log(1+x)-log(1-x))/2
        // instead.
-       const ex arg_pt = arg.subs(rel);
+       const ex arg_pt = arg.subs(rel, subs_options::no_pattern);
        if (!(arg_pt).info(info_flags::real))
                throw do_taylor();     // Im(x) != 0
        if ((arg_pt).info(info_flags::real) && abs(arg_pt)<_ex1)
@@ -1036,7 +1039,7 @@ static ex atanh_series(const ex &arg,
                const symbol &s = ex_to<symbol>(rel.lhs());
                const ex &point = rel.rhs();
                const symbol foo;
-               const ex replarg = series(atanh(arg), s==foo, order).subs(foo==point);
+               const ex replarg = series(atanh(arg), s==foo, order).subs(foo==point, subs_options::no_pattern);
                ex Order0correction = replarg.op(0)+csgn(I*arg)*Pi*I*_ex1_2;
                if (arg_pt<_ex0)
                        Order0correction += log((arg_pt+_ex_1)/(arg_pt+_ex1))*_ex1_2;