X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=ginac%2Finifcns.cpp;h=f7d2864ef9ae64035eae269d140b6c36b6d41169;hp=5eb4466cc72b710865d8842e4aa935fecdc858f5;hb=af0c47009ca7a15af966430bdf1a72fe05c1c6f9;hpb=9eab44408b9213d8909b7a9e525f404ad06064dd diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp index 5eb4466c..f7d2864e 100644 --- a/ginac/inifcns.cpp +++ b/ginac/inifcns.cpp @@ -3,7 +3,7 @@ * Implementation of GiNaC's initially known functions. */ /* - * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany + * GiNaC Copyright (C) 1999-2000 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 @@ -33,51 +33,139 @@ #include "numeric.h" #include "power.h" #include "relational.h" -#include "series.h" +#include "pseries.h" #include "symbol.h" +#include "utils.h" +#ifndef NO_NAMESPACE_GINAC namespace GiNaC { +#endif // ndef NO_NAMESPACE_GINAC + +////////// +// absolute value +////////// + +static ex abs_evalf(const ex & x) +{ + BEGIN_TYPECHECK + TYPECHECK(x,numeric) + END_TYPECHECK(abs(x)) + + return abs(ex_to_numeric(x)); +} + +static ex abs_eval(const ex & x) +{ + if (is_ex_exactly_of_type(x, numeric)) + return abs(ex_to_numeric(x)); + else + return abs(x).hold(); +} + +REGISTER_FUNCTION(abs, eval_func(abs_eval). + evalf_func(abs_evalf)); + + +////////// +// Complex sign +////////// + +static ex csgn_evalf(const ex & x) +{ + BEGIN_TYPECHECK + TYPECHECK(x,numeric) + END_TYPECHECK(csgn(x)) + + return csgn(ex_to_numeric(x)); +} + +static ex csgn_eval(const ex & x) +{ + if (is_ex_exactly_of_type(x, numeric)) + return csgn(ex_to_numeric(x)); + + if (is_ex_exactly_of_type(x, mul)) { + numeric oc = ex_to_numeric(x.op(x.nops()-1)); + if (oc.is_real()) { + if (oc > 0) + // csgn(42*x) -> csgn(x) + return csgn(x/oc).hold(); + else + // csgn(-42*x) -> -csgn(x) + return -csgn(x/oc).hold(); + } + if (oc.real().is_zero()) { + if (oc.imag() > 0) + // csgn(42*I*x) -> csgn(I*x) + return csgn(I*x/oc).hold(); + else + // csgn(-42*I*x) -> -csgn(I*x) + return -csgn(I*x/oc).hold(); + } + } + + return csgn(x).hold(); +} + +static ex csgn_series(const ex & x, const relational & rel, int order) +{ + const ex x_pt = x.subs(rel); + if (x_pt.info(info_flags::numeric)) { + if (ex_to_numeric(x_pt).real().is_zero()) + throw (std::domain_error("csgn_series(): on imaginary axis")); + epvector seq; + seq.push_back(expair(csgn(x_pt), _ex0())); + return pseries(rel,seq); + } + epvector seq; + seq.push_back(expair(csgn(x_pt), _ex0())); + return pseries(rel,seq); +} + +REGISTER_FUNCTION(csgn, eval_func(csgn_eval). + evalf_func(csgn_evalf). + series_func(csgn_series)); ////////// // dilogarithm ////////// -ex Li2_eval(ex const & x) +static ex Li2_eval(const ex & x) { if (x.is_zero()) return x; - if (x.is_equal(exONE())) - return power(Pi, 2) / 6; - if (x.is_equal(exMINUSONE())) - return -power(Pi, 2) / 12; + if (x.is_equal(_ex1())) + return power(Pi, _ex2()) / _ex6(); + if (x.is_equal(_ex_1())) + return -power(Pi, _ex2()) / _ex12(); return Li2(x).hold(); } -REGISTER_FUNCTION(Li2, Li2_eval, NULL, NULL, NULL); +REGISTER_FUNCTION(Li2, eval_func(Li2_eval)); ////////// // trilogarithm ////////// -ex Li3_eval(ex const & x) +static ex Li3_eval(const ex & x) { if (x.is_zero()) return x; return Li3(x).hold(); } -REGISTER_FUNCTION(Li3, Li3_eval, NULL, NULL, NULL); +REGISTER_FUNCTION(Li3, eval_func(Li3_eval)); ////////// // factorial ////////// -ex factorial_evalf(ex const & x) +static ex factorial_evalf(const ex & x) { return factorial(x).hold(); } -ex factorial_eval(ex const & x) +static ex factorial_eval(const ex & x) { if (is_ex_exactly_of_type(x, numeric)) return factorial(ex_to_numeric(x)); @@ -85,18 +173,19 @@ ex factorial_eval(ex const & x) return factorial(x).hold(); } -REGISTER_FUNCTION(factorial, factorial_eval, factorial_evalf, NULL, NULL); +REGISTER_FUNCTION(factorial, eval_func(factorial_eval). + evalf_func(factorial_evalf)); ////////// // binomial ////////// -ex binomial_evalf(ex const & x, ex const & y) +static ex binomial_evalf(const ex & x, const ex & y) { return binomial(x, y).hold(); } -ex binomial_eval(ex const & x, ex const &y) +static ex binomial_eval(const ex & x, const ex &y) { if (is_ex_exactly_of_type(x, numeric) && is_ex_exactly_of_type(y, numeric)) return binomial(ex_to_numeric(x), ex_to_numeric(y)); @@ -104,18 +193,19 @@ ex binomial_eval(ex const & x, ex const &y) return binomial(x, y).hold(); } -REGISTER_FUNCTION(binomial, binomial_eval, binomial_evalf, NULL, NULL); +REGISTER_FUNCTION(binomial, eval_func(binomial_eval). + evalf_func(binomial_evalf)); ////////// // Order term function (for truncated power series) ////////// -ex Order_eval(ex const & x) +static ex Order_eval(const ex & x) { if (is_ex_exactly_of_type(x, numeric)) { // O(c)=O(1) - return Order(exONE()).hold(); + return Order(_ex1()).hold(); } else if (is_ex_exactly_of_type(x, mul)) { @@ -129,18 +219,43 @@ ex Order_eval(ex const & x) return Order(x).hold(); } -ex Order_series(ex const & x, symbol const & s, ex const & point, int order) +static ex Order_series(const ex & x, const relational & r, int order) { - // Just wrap the function into a series object + // Just wrap the function into a pseries object epvector new_seq; - new_seq.push_back(expair(Order(exONE()), numeric(min(x.ldegree(s), order)))); - return series(s, point, new_seq); + GINAC_ASSERT(is_ex_exactly_of_type(r.lhs(),symbol)); + const symbol *s = static_cast(r.lhs().bp); + new_seq.push_back(expair(Order(_ex1()), numeric(min(x.ldegree(*s), order)))); + return pseries(r, new_seq); +} + +// Differentiation is handled in function::derivative because of its special requirements + +REGISTER_FUNCTION(Order, eval_func(Order_eval). + series_func(Order_series)); + +////////// +// Inert partial differentiation operator +////////// + +static ex Derivative_eval(const ex & f, const ex & l) +{ + if (!is_ex_exactly_of_type(f, function)) { + throw(std::invalid_argument("Derivative(): 1st argument must be a function")); + } + if (!is_ex_exactly_of_type(l, lst)) { + throw(std::invalid_argument("Derivative(): 2nd argument must be a list")); + } + return Derivative(f, l).hold(); } -REGISTER_FUNCTION(Order, Order_eval, NULL, NULL, Order_series); +REGISTER_FUNCTION(Derivative, eval_func(Derivative_eval)); -/** linear solve. */ -ex lsolve(ex const &eqns, ex const &symbols) +////////// +// Solve linear system +////////// + +ex lsolve(const ex &eqns, const ex &symbols) { // solve a system of linear equations if (eqns.info(info_flags::relation_equal)) { @@ -149,8 +264,8 @@ ex lsolve(ex const &eqns, ex const &symbols) } ex sol=lsolve(lst(eqns),lst(symbols)); - ASSERT(sol.nops()==1); - ASSERT(is_ex_exactly_of_type(sol.op(0),relational)); + GINAC_ASSERT(sol.nops()==1); + GINAC_ASSERT(is_ex_exactly_of_type(sol.op(0),relational)); return sol.op(0).op(1); // return rhs of first solution } @@ -159,7 +274,7 @@ ex lsolve(ex const &eqns, ex const &symbols) if (!eqns.info(info_flags::list)) { throw(std::invalid_argument("lsolve: 1st argument must be a list")); } - for (int i=0; i