From 4f77e0c3f775040168c74d0488a16ac0419c4114 Mon Sep 17 00:00:00 2001 From: Christian Bauer Date: Wed, 27 Jun 2001 00:26:24 +0000 Subject: [PATCH] added note about the necessity of dirac_ONE()/color_ONE() --- doc/tutorial/ginac.texi | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/doc/tutorial/ginac.texi b/doc/tutorial/ginac.texi index 5934347c..2680ac7a 100644 --- a/doc/tutorial/ginac.texi +++ b/doc/tutorial/ginac.texi @@ -2265,8 +2265,14 @@ The unity element of a Clifford algebra is constructed by ex dirac_ONE(unsigned char rl = 0); @end example +@strong{Note:} You must always use @code{dirac_ONE()} when referring to +multiples of the unity element, even though it's customary to omit it. +E.g. instead of @code{dirac_gamma(mu)*(dirac_slash(q,4)+m)} you have to +write @code{dirac_gamma(mu)*(dirac_slash(q,4)+m*dirac_ONE())}. Otherwise, +GiNaC may produce incorrect results. + @cindex @code{dirac_gamma5()} -and there's a special element @samp{gamma5} that commutes with all other +There's a special element @samp{gamma5} that commutes with all other gammas and in 4 dimensions equals @samp{gamma~0 gamma~1 gamma~2 gamma~3}, provided by @@ -2429,9 +2435,15 @@ The unity element of a color algebra is constructed by ex color_ONE(unsigned char rl = 0); @end example +@strong{Note:} You must always use @code{color_ONE()} when referring to +multiples of the unity element, even though it's customary to omit it. +E.g. instead of @code{color_T(a)*(color_T(b)*indexed(X,b)+1)} you have to +write @code{color_T(a)*(color_T(b)*indexed(X,b)+color_ONE())}. Otherwise, +GiNaC may produce incorrect results. + @cindex @code{color_d()} @cindex @code{color_f()} -and the functions +The functions @example ex color_d(const ex & a, const ex & b, const ex & c); @@ -3898,8 +3910,6 @@ GiNaC contains the following predefined mathematical functions: @tab binomial coefficients @item @code{Order(x)} @tab order term function in truncated power series -@item @code{Derivative(x, l)} -@tab inert partial differentiation operator (used internally) @end multitable @end cartouche -- 2.44.0