From 47136d078ba37491faf3310b72b0069099480fc8 Mon Sep 17 00:00:00 2001 From: "Vladimir V. Kisil" Date: Wed, 31 Jul 2013 15:14:32 +0100 Subject: [PATCH 5/9] Add specific-tailored expand to GiNaC functions. This patch adds expand() methods which can be tailored to particular function. For example, exp(a*b).expand() -> exp(a)*exp(b) and log(p*q).expand() -> log(p) + log(q). Signed-off-by: Vladimir V. Kisil --- check/exam_inifcns.cpp | 58 +++++++++++++++++++++++++++++++++++++++- ginac/function.cppy | 42 +++++++++++++++++++++-------- ginac/function.hppy | 5 ++++ ginac/function.py | 2 +- ginac/inifcns.cpp | 21 +++++++++++++++ ginac/inifcns_trans.cpp | 70 +++++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 185 insertions(+), 13 deletions(-) diff --git a/check/exam_inifcns.cpp b/check/exam_inifcns.cpp index 994aa34..424aa26 100644 --- a/check/exam_inifcns.cpp +++ b/check/exam_inifcns.cpp @@ -222,6 +222,7 @@ static unsigned inifcns_consist_zeta() static unsigned inifcns_consist_abs() { unsigned result = 0; + symbol z("z"); realsymbol a("a"), b("b"), x("x"), y("y"); possymbol p("p"); @@ -242,6 +243,59 @@ static unsigned inifcns_consist_abs() if (!abs(pow(x+I*y,a+I*b)).eval().is_equal(abs(pow(x+I*y,a+I*b)))) ++result; + // check expansion of abs + if (!abs(-7*z*a*p).expand().is_equal(7*abs(z)*abs(a)*p)) + ++result; + + return result; +} + +static unsigned inifcns_consist_exp() +{ + unsigned result = 0; + symbol a("a"), b("b"); + + if (!exp(a+b).expand().is_equal(exp(a)*exp(b))) + ++result; + + // shall not be expanded since the arg is not add + if (!exp(pow(a+b,2)).expand().is_equal(exp(pow(a+b,2)))) + ++result; + + // expand now + if (!exp(pow(a+b,2)).expand(expand_options::expand_function_args) + .is_equal(exp(a*a)*exp(b*b)*exp(2*a*b))) + ++result; + + return result; +} + +static unsigned inifcns_consist_log() +{ + unsigned result = 0; + symbol z("a"), w("b"); + realsymbol a("a"), b("b"); + possymbol p("p"), q("q"); + + // do not expand + if (!log(z*w).expand().is_equal(log(z*w))) + ++result; + + // do not expand + if (!log(a*b).expand().is_equal(log(a*b))) + ++result; + + // shall expand + if (!log(p*q).expand().is_equal(log(p) +log(q))) + ++result; + + // a bit more complicated + ex e1=log(-7*p*pow(q,3)*a*pow(b,2)*z*w).expand(); + ex e2=log(7)+log(p)+log(pow(q,3))+log(-z*a*w*pow(b,2)); + if (!e1.is_equal(e2)) + ++result; + + return result; } static unsigned inifcns_consist_various() @@ -253,7 +307,7 @@ static unsigned inifcns_consist_various() clog << "ERROR: binomial(n,0) != 1" << endl; ++result; } - + return result; } @@ -268,6 +322,8 @@ unsigned exam_inifcns() result += inifcns_consist_psi(); cout << '.' << flush; result += inifcns_consist_zeta(); cout << '.' << flush; result += inifcns_consist_abs(); cout << '.' << flush; + result += inifcns_consist_exp(); cout << '.' << flush; + result += inifcns_consist_log(); cout << '.' << flush; result += inifcns_consist_various(); cout << '.' << flush; return result; diff --git a/ginac/function.cppy b/ginac/function.cppy index fb83cdc..1b76184 100644 --- a/ginac/function.cppy +++ b/ginac/function.cppy @@ -78,8 +78,8 @@ void function_options::initialize() { set_name("unnamed_function", "\\\\mbox{unnamed}"); nparams = 0; - eval_f = evalf_f = real_part_f = imag_part_f = conjugate_f = derivative_f - = power_f = series_f = 0; + eval_f = evalf_f = real_part_f = imag_part_f = conjugate_f = expand_f + = derivative_f = power_f = series_f = 0; evalf_params_first = true; use_return_type = false; eval_use_exvector_args = false; @@ -87,6 +87,7 @@ void function_options::initialize() conjugate_use_exvector_args = false; real_part_use_exvector_args = false; imag_part_use_exvector_args = false; + expand_use_exvector_args = false; derivative_use_exvector_args = false; power_use_exvector_args = false; series_use_exvector_args = false; @@ -360,15 +361,6 @@ next_context: } } -ex function::expand(unsigned options) const -{ - // Only expand arguments when asked to do so - if (options & expand_options::expand_function_args) - return inherited::expand(options); - else - return (options == 0) ? setflag(status_flags::expanded) : *this; -} - ex function::eval(int level) const { if (level>1) { @@ -756,6 +748,34 @@ ex function::power(const ex & power_param) const // power of function throw(std::logic_error("function::power(): no power function defined")); } +ex function::expand(unsigned options) const +{ + GINAC_ASSERT(serial & function::registered_functions() { static std::vector rf = std::vector(); diff --git a/ginac/function.hppy b/ginac/function.hppy index e7ec83e..fa17813 100644 --- a/ginac/function.hppy +++ b/ginac/function.hppy @@ -57,6 +57,7 @@ typedef ex (* evalf_funcp)(); typedef ex (* conjugate_funcp)(); typedef ex (* real_part_funcp)(); typedef ex (* imag_part_funcp)(); +typedef ex (* expand_funcp)(); typedef ex (* derivative_funcp)(); typedef ex (* power_funcp)(); typedef ex (* series_funcp)(); @@ -69,6 +70,7 @@ typedef ex (* evalf_funcp_@N@)( @args@ ); typedef ex (* conjugate_funcp_@N@)( @args@ ); typedef ex (* real_part_funcp_@N@)( @args@ ); typedef ex (* imag_part_funcp_@N@)( @args@ ); +typedef ex (* expand_funcp_@N@)( @args@, unsigned ); typedef ex (* derivative_funcp_@N@)( @args@, unsigned ); typedef ex (* power_funcp_@N@)( @args@, const ex & ); typedef ex (* series_funcp_@N@)( @args@, const relational &, int, unsigned ); @@ -81,6 +83,7 @@ typedef void (* print_funcp_@N@)( @args@, const print_context & ); +++ for fp in "eval evalf conjugate real_part imag_part".split(): typedef ex (* @fp@_funcp_exvector)(const exvector &); --- +typedef ex (* expand_funcp_exvector)(const exvector &, unsigned); typedef ex (* derivative_funcp_exvector)(const exvector &, unsigned); typedef ex (* power_funcp_exvector)(const exvector &, const ex &); typedef ex (* series_funcp_exvector)(const exvector &, const relational &, int, unsigned); @@ -151,6 +154,7 @@ protected: conjugate_funcp conjugate_f; real_part_funcp real_part_f; imag_part_funcp imag_part_f; + expand_funcp expand_f; derivative_funcp derivative_f; power_funcp power_f; series_funcp series_f; @@ -172,6 +176,7 @@ protected: bool conjugate_use_exvector_args; bool real_part_use_exvector_args; bool imag_part_use_exvector_args; + bool expand_use_exvector_args; bool derivative_use_exvector_args; bool power_use_exvector_args; bool series_use_exvector_args; diff --git a/ginac/function.py b/ginac/function.py index 6ceb254..0ecb918 100755 --- a/ginac/function.py +++ b/ginac/function.py @@ -2,7 +2,7 @@ # encoding: utf-8 maxargs = 14 -methods = "eval evalf conjugate real_part imag_part derivative power series print".split() +methods = "eval evalf conjugate real_part imag_part expand derivative power series print".split() import sys, os, optparse sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..', 'scripts')) diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp index 08f9b02..6add43d 100644 --- a/ginac/inifcns.cpp +++ b/ginac/inifcns.cpp @@ -206,6 +206,26 @@ static ex abs_eval(const ex & arg) return abs(arg).hold(); } +static ex abs_expand(const ex & arg, unsigned options) +{ + if (is_exactly_a(arg)) { + exvector prodseq; + prodseq.reserve(arg.nops()); + for (const_iterator i = arg.begin(); i != arg.end(); ++i) { + if (options & expand_options::expand_function_args) + prodseq.push_back(abs(i->expand(options))); + else + prodseq.push_back(abs(*i)); + } + return (new mul(prodseq))->setflag(status_flags::dynallocated | status_flags::expanded); + } + + if (options & expand_options::expand_function_args) + return abs(arg.expand(options)).hold(); + else + return abs(arg).hold(); +} + static void abs_print_latex(const ex & arg, const print_context & c) { c.s << "{|"; arg.print(c); c.s << "|}"; @@ -242,6 +262,7 @@ static ex abs_power(const ex & arg, const ex & exp) REGISTER_FUNCTION(abs, eval_func(abs_eval). evalf_func(abs_evalf). + expand_func(abs_expand). print_func(abs_print_latex). print_func(abs_print_csrc_float). print_func(abs_print_csrc_float). diff --git a/ginac/inifcns_trans.cpp b/ginac/inifcns_trans.cpp index 10a3675..0d4904a 100644 --- a/ginac/inifcns_trans.cpp +++ b/ginac/inifcns_trans.cpp @@ -24,6 +24,8 @@ #include "inifcns.h" #include "ex.h" #include "constant.h" +#include "add.h" +#include "mul.h" #include "numeric.h" #include "power.h" #include "operators.h" @@ -81,6 +83,26 @@ static ex exp_eval(const ex & x) return exp(x).hold(); } +static ex exp_expand(const ex & arg, unsigned options) +{ + ex exp_arg; + if (options & expand_options::expand_function_args) + exp_arg = arg.expand(options); + else + exp_arg=arg; + + if (is_exactly_a(exp_arg)) { + exvector prodseq; + prodseq.reserve(exp_arg.nops()); + for (const_iterator i = exp_arg.begin(); i != exp_arg.end(); ++i) + prodseq.push_back(exp(*i)); + + return (new mul(prodseq))->setflag(status_flags::dynallocated | status_flags::expanded); + } + + return exp(exp_arg).hold(); +} + static ex exp_deriv(const ex & x, unsigned deriv_param) { GINAC_ASSERT(deriv_param==0); @@ -107,6 +129,7 @@ static ex exp_conjugate(const ex & x) REGISTER_FUNCTION(exp, eval_func(exp_eval). evalf_func(exp_evalf). + expand_func(exp_expand). derivative_func(exp_deriv). real_part_func(exp_real_part). imag_part_func(exp_imag_part). @@ -265,6 +288,52 @@ static ex log_imag_part(const ex & x) return atan2(GiNaC::imag_part(x), GiNaC::real_part(x)); } +static ex log_expand(const ex & arg, unsigned options) +{ + if (is_exactly_a(arg) && !arg.info(info_flags::indefinite)) { + exvector sumseq; + exvector prodseq; + sumseq.reserve(arg.nops()); + prodseq.reserve(arg.nops()); + bool possign=true; + + // searching for positive/negative factors + for (const_iterator i = arg.begin(); i != arg.end(); ++i) { + ex e; + if (options & expand_options::expand_function_args) + e=i->expand(options); + else + e=*i; + if (e.info(info_flags::positive)) + sumseq.push_back(log(e)); + else if (e.info(info_flags::negative)) { + sumseq.push_back(log(-e)); + possign = !possign; + } else + prodseq.push_back(e); + } + + if (sumseq.size() > 0) { + ex newarg; + if (options & expand_options::expand_function_args) + newarg=((possign?_ex1:_ex_1)*mul(prodseq)).expand(options); + else { + newarg=(possign?_ex1:_ex_1)*mul(prodseq); + ex_to(newarg).setflag(status_flags::purely_indefinite); + } + return add(sumseq)+log(newarg); + } else { + if (!(options & expand_options::expand_function_args)) + ex_to(arg).setflag(status_flags::purely_indefinite); + } + } + + if (options & expand_options::expand_function_args) + return log(arg.expand(options)).hold(); + else + return log(arg).hold(); +} + static ex log_conjugate(const ex & x) { // conjugate(log(x))==log(conjugate(x)) unless on the branch cut which @@ -281,6 +350,7 @@ static ex log_conjugate(const ex & x) REGISTER_FUNCTION(log, eval_func(log_eval). evalf_func(log_evalf). + expand_func(log_expand). derivative_func(log_deriv). series_func(log_series). real_part_func(log_real_part). -- 1.8.4.rc3