From e35374d3a77329ac62f753f86f60d56cef48db13 Mon Sep 17 00:00:00 2001 From: "Vladimir V. Kisil" Date: Thu, 1 Aug 2013 14:37:45 +0100 Subject: [PATCH 7/9] Improvements to function abs and power::info. Abs now can evaluate conjugates and step function. Power with real base and even-integer exponents reports that it is non-negative. Signed-off-by: Vladimir V. Kisil --- check/exam_inifcns.cpp | 6 ++++++ ginac/inifcns.cpp | 6 ++++++ ginac/power.cpp | 2 ++ 3 files changed, 14 insertions(+) diff --git a/check/exam_inifcns.cpp b/check/exam_inifcns.cpp index 2191172..12a6c02 100644 --- a/check/exam_inifcns.cpp +++ b/check/exam_inifcns.cpp @@ -247,6 +247,12 @@ static unsigned inifcns_consist_abs() if (!abs(-7*z*a*p).expand().is_equal(7*abs(z)*abs(a)*p)) ++result; + if (!abs(z.conjugate()).eval().is_equal(abs(z))) + ++result; + + if (!abs(step(z)).eval().is_equal(step(z))) + ++result; + return result; } diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp index 6add43d..168102b 100644 --- a/ginac/inifcns.cpp +++ b/ginac/inifcns.cpp @@ -203,6 +203,12 @@ static ex abs_eval(const ex & arg) if (is_exactly_a(arg) && (arg.op(0).info(info_flags::positive) || arg.op(1).info(info_flags::real))) return pow(abs(arg.op(0)), arg.op(1).real_part()); + if (is_ex_the_function(arg, conjugate_function)) + return abs(arg.op(0)); + + if (is_ex_the_function(arg, step)) + return arg; + return abs(arg).hold(); } diff --git a/ginac/power.cpp b/ginac/power.cpp index ec3717e..f0673ae 100644 --- a/ginac/power.cpp +++ b/ginac/power.cpp @@ -242,6 +242,8 @@ bool power::info(unsigned inf) const return (flags & status_flags::expanded); case info_flags::positive: return basis.info(info_flags::positive) && exponent.info(info_flags::real); + case info_flags::nonnegative: + return basis.info(info_flags::real) && exponent.info(info_flags::integer) && exponent.info(info_flags::even); case info_flags::has_indices: { if (flags & status_flags::has_indices) return true; -- 1.8.4.rc3