% Copyright 2007 by Mark Wibrow
%
% This file may be distributed and/or modified
%
% 1. under the LaTeX Project Public License and/or
% 2. under the GNU Public License.
%
% See the file doc/generic/pgf/licenses/LICENSE for more details.

% This file defines the mathematical functions and operators.
%
% Version 1.4142135 25/8/2008

% add function.
%
\pgfmathdeclarefunction{add}{2}{%
    \begingroup%
    \pgfmath@x=#1pt\relax%
    \pgfmath@y=#2pt\relax%
    \advance\pgfmath@x by\pgfmath@y%
    \pgfmath@returnone\pgfmath@x%
  \endgroup%
}


% subtract function.
%
\pgfmathdeclarefunction{subtract}{2}{%
    \begingroup%
    \pgfmath@x=#1pt\relax%
    \pgfmath@y=#2pt\relax%
    \advance\pgfmath@x by-\pgfmath@y%
    \pgfmath@returnone\pgfmath@x%
  \endgroup%
}

% neg function.
%
\pgfmathdeclarefunction{neg}{1}{%
    \begingroup%
        \pgfmath@x=-#1pt\relax%
        \edef\pgfmathresult{\pgfmath@tonumber{\pgfmath@x}}%
        \pgfmath@smuggleone\pgfmathresult%
    \endgroup%
}
% change the precedence for neg.
% Otherwise, unary minus and exponentiation won't have the correct precedence
% (test '-2^2')
\def\pgfmath@operation@neg@precedence{500}

% multiply function.
%
\pgfmathdeclarefunction{multiply}{2}{%
  \begingroup%
    \pgfmath@x=#1pt\relax%
    \pgfmath@y=#2pt\relax%
    \pgfmath@x=\pgfmath@tonumber{\pgfmath@y}\pgfmath@x%
    \pgfmath@returnone\pgfmath@x%
  \endgroup%
}

% divide function.
%
\newif\ifpgfmath@divide@period

\pgfmathdeclarefunction{divide}{2}{%
    \begingroup%
        \pgfmath@x=#1pt\relax%
        \pgfmath@y=#2pt\relax%
        \let\pgfmath@sign=\pgfmath@empty%
        \ifdim0pt=\pgfmath@y%
            \pgfmath@error{You've asked me to divide `#1' by `#2', %
                but I cannot divide any number by `#2'}%
        \fi%
        \afterassignment\pgfmath@xa%
        \c@pgfmath@counta\the\pgfmath@y\relax%
        \ifdim0pt=\pgfmath@xa%
            \divide\pgfmath@x by\c@pgfmath@counta%
        \else%
            \ifdim0pt>\pgfmath@x%
                \def\pgfmath@sign{-}%
                \pgfmath@x=-\pgfmath@x%
            \fi%
            \ifdim0pt>\pgfmath@y%
                \expandafter\def\expandafter\pgfmath@sign\expandafter{\pgfmath@sign-}%
                \pgfmath@y=-\pgfmath@y%
            \fi%
            \ifdim1pt>\pgfmath@y%
                \pgfmathreciprocal@{\pgfmath@tonumber{\pgfmath@y}}%
                \pgfmath@x=\pgfmath@sign\pgfmathresult\pgfmath@x%
            \else%
                \def\pgfmathresult{0}%
                \pgfmath@divide@periodtrue%
                \c@pgfmath@counta=0\relax%
                \pgfmathdivide@@%
                \pgfmath@x=\pgfmath@sign\pgfmathresult pt\relax%
            \fi%
        \fi%
        \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

\def\pgfmath@small@number{0.00002}

\def\pgfmathdivide@@{%
    \let\pgfmath@next=\relax%
    \ifdim\pgfmath@small@number pt<\pgfmath@x%
        \ifdim\pgfmath@small@number pt<\pgfmath@y%
            \ifdim\pgfmath@y>\pgfmath@x%
                \ifpgfmath@divide@period%
                    \expandafter\def\expandafter\pgfmathresult\expandafter{\pgfmathresult.}%
                    \pgfmath@divide@periodfalse%
                \fi%
                \pgfmathdivide@dimenbyten\pgfmath@y%
                \ifdim\pgfmath@y>\pgfmath@x%
                    \expandafter\def\expandafter\pgfmathresult\expandafter{\pgfmathresult0}%
                \fi%
            \else%
                \c@pgfmath@counta=\pgfmath@x%
                \c@pgfmath@countb=\pgfmath@y%
                \divide\c@pgfmath@counta by\c@pgfmath@countb%
                \pgfmath@ya=\c@pgfmath@counta\pgfmath@y%
                \advance\pgfmath@x by-\pgfmath@ya%
                \def\pgfmath@next{%
                    \toks0=\expandafter{\pgfmathresult}%
                    \edef\pgfmathresult{\the\toks0 \the\c@pgfmath@counta}%
                }%
                \ifpgfmath@divide@period
                \else
                    % we are behind the period. It may happen that the
                    % result is more than one digit - in that case,
                    % introduce special handling:
                    \ifnum\c@pgfmath@counta>9 %
                        \expandafter\pgfmathdivide@advance@last@digit\pgfmathresult CCCCC\@@
                        \advance\c@pgfmath@counta by-10 %
                        \ifnum\c@pgfmath@counta=0
                            \let\pgfmath@next=\relax
                        \fi
                    \fi
                \fi
                \pgfmath@next
            \fi%
            \let\pgfmath@next=\pgfmathdivide@@%
        \fi%
    \fi%
    \pgfmath@next%
}

% advances the last digit found in the number. Any missing digits are
% supposed to be filled with 'C'.
\def\pgfmathdivide@advance@last@digit#1.#2#3#4#5#6#7\@@{%
    \pgfmath@ya=\pgfmathresult pt %
    \if#2C%
        \pgfmath@xa=1pt %
    \else
        \if#3C%
            \pgfmath@xa=0.1pt %
        \else
            \if#4C%
                \pgfmath@xa=0.01pt %
            \else
                \if#5C%
                    \pgfmath@xa=0.001pt %
                \else
                    \if#6C%
                        \pgfmath@xa=0.0001pt %
                    \else
                        \pgfmath@xa=0.00001pt %
                    \fi
                \fi
            \fi
        \fi
    \fi
    \advance\pgfmath@ya by\pgfmath@xa
    \edef\pgfmathresult{\pgfmath@tonumber@notrailingzero\pgfmath@ya}%
}%

{
\catcode`\p=12
\catcode`\t=12
\gdef\Pgf@geT@NO@TRAILING@ZERO#1.#2pt{%
    #1.%
    \ifnum#2=0 \else #2\fi
}
}
\def\pgfmath@tonumber@notrailingzero#1{\expandafter\Pgf@geT@NO@TRAILING@ZERO\the#1}


\def\pgfmathdivide@dimenbyten#1{%
    \edef\pgfmath@temp{\pgfmath@tonumber{#1}}%
    \expandafter\pgfmathdivide@@dimenbyten\pgfmath@temp\@@#1\@@}
\def\pgfmathdivide@@dimenbyten#1.#2\@@#3\@@{%
    \pgfmath@tempcnta=#1\relax%
    \divide\pgfmath@tempcnta by10\relax%
    \pgfmath@tempcntb=\pgfmath@tempcnta%
    \multiply\pgfmath@tempcnta by-10\relax%
    \advance\pgfmath@tempcnta by#1\relax%
    #3=\the\pgfmath@tempcntb.\the\pgfmath@tempcnta#2pt\relax%
}


% reciprocal function.
%
\pgfmathdeclarefunction{reciprocal}{1}{%
    \begingroup%
        \expandafter\pgfmath@x#1pt\relax%
        \ifdim\pgfmath@x=0pt\relax%
            \pgfmath@error{You asked me to calculate `1/#1', but I cannot divide any number by zero}{}%
        \fi%
        \edef\pgfmath@reciprocaltemp{\pgfmath@tonumber{\pgfmath@x}}%
        \expandafter\pgfmathreciprocal@@\pgfmath@reciprocaltemp0000000\pgfmath@}
\def\pgfmathreciprocal@@#1.#2#3#4#5#6#7\pgfmath@{%
        \c@pgfmath@counta#2#3#4#5#6\relax%
        % If the number is an integer, use TeX arithmetic.
        \ifnum\c@pgfmath@counta=0\relax%
            \pgfmath@x1pt\relax%
            \divide\pgfmath@x#1\relax%
        \else%
            \ifnum#1>100\relax%
                \c@pgfmath@counta#1#2#3#4\relax%
                \c@pgfmath@countb1000000000\relax%
                \divide\c@pgfmath@countb\c@pgfmath@counta%
                \c@pgfmath@counta\c@pgfmath@countb%
                \divide\c@pgfmath@counta10000\relax%
                \pgfmath@x\c@pgfmath@counta pt\relax%
                \multiply\c@pgfmath@counta-10000\relax%
                \advance\c@pgfmath@countb\c@pgfmath@counta%
                \pgfmath@y\c@pgfmath@countb pt\relax%
                \divide\pgfmath@y1000000\relax%
                \advance\pgfmath@x\pgfmath@y%
            \else%
                \c@pgfmath@counta#1#2#3#4#5#6\relax%
                \c@pgfmath@countb1000000000\relax%
                \divide\c@pgfmath@countb\c@pgfmath@counta%
                \c@pgfmath@counta\c@pgfmath@countb%
                \divide\c@pgfmath@counta10000\relax%
                \pgfmath@x\c@pgfmath@counta pt\relax%
                \multiply\c@pgfmath@counta-10000\relax%
                \advance\c@pgfmath@countb\c@pgfmath@counta%
                \pgfmath@y\c@pgfmath@countb pt\relax%
                \pgfmath@y.1\pgfmath@y% Yes! This way is more accurate. Go figure...
                \pgfmath@y.1\pgfmath@y%
                \pgfmath@y.1\pgfmath@y%
                \pgfmath@y.1\pgfmath@y%
                \advance\pgfmath@x\pgfmath@y%
            \fi%
        \fi%
        \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

% div function.
%
\pgfmathdeclarefunction{div}{2}{%
    \begingroup%
        \pgfmathdivide@{#1}{#2}%
        \ifdim\pgfmathresult pt<0pt\relax%
            \pgfmathceil@{\pgfmathresult}%
        \else%
            \pgfmathfloor@{\pgfmathresult}%
        \fi%
        \afterassignment\pgfmath@gobbletilpgfmath@%
        \c@pgfmath@counta=\pgfmathresult\relax\pgfmath@%
        \edef\pgfmathresult{\the\c@pgfmath@counta}%
        \pgfmath@smuggleone\pgfmathresult%
    \endgroup%
}

% mod function.
%
\pgfmathdeclarefunction{mod}{2}{%
  \begingroup%
    \pgfmath@xa#1pt%
    \pgfmath@xb#2pt%
    \pgfmath@x\pgfmath@xa%
    \c@pgfmath@counta\pgfmath@xa%
    \c@pgfmath@countb\pgfmath@xb%
    \divide\c@pgfmath@counta\c@pgfmath@countb%
    \multiply\pgfmath@xb\c@pgfmath@counta%
    \advance\pgfmath@x-\pgfmath@xb%
    \pgfmath@returnone\pgfmath@x%
  \endgroup%
}

% Mod function (never negative).
%
\pgfmathdeclarefunction{Mod}{2}{%
    \begingroup%
        \pgfmathmod@{#1}{#2}%
        \pgfmath@x=\pgfmathresult pt\relax%
        \ifdim\pgfmath@x<0pt\relax%
            \advance\pgfmath@x by#2pt\relax%
        \fi%
        \edef\pgfmathresult{\pgfmath@tonumber{\pgfmath@x}}%
        \pgfmath@smuggleone\pgfmathresult%
    \endgroup%
}

% abs function.
%
\pgfmathdeclarefunction{abs}{1}{%
    \begingroup%
        \expandafter\pgfmath@x#1pt\relax%
        \ifdim\pgfmath@x<0pt\relax%
            \pgfmath@x-\pgfmath@x%
        \fi%
    \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

% sign(x)
\pgfmathdeclarefunction{sign}{1}{%
  \begingroup
    \ifdim#1pt>0sp %
      \def\pgfmathresult{1}%
    \else
      \ifdim#1pt=0sp %
        \def\pgfmathresult{0}%
      \else
        \def\pgfmathresult{-1}%
      \fi
    \fi
    \pgfmath@smuggleone\pgfmathresult
  \endgroup
}

% e constant.
%
\pgfmathdeclarefunction{e}{0}{\def\pgfmathresult{2.718281828}}

% ln function.
%
% This is based on an algorithm due to Rouben Rostamian and
% uses coefficients contributed by Alain Matthes.
%
\pgfmathdeclarefunction{ln}{1}{%
    \begingroup%
        \expandafter\pgfmath@x#1pt\relax%
        \ifdim\pgfmath@x>0pt\else%
            \pgfmath@error{I cannot calculate the logarithm of `#1'}{}%
        \fi%
        \c@pgfmath@counta=0\relax%
        \ifdim\pgfmath@x>2pt\relax%
            \ifdim\pgfmath@x<128pt\relax%
                \ifdim\pgfmath@x<8pt\relax%
                    \ifdim\pgfmath@x<4pt\relax%
                        \divide\pgfmath@x by2\relax%
                        \c@pgfmath@counta=1\relax%
                    \else%
                        \divide\pgfmath@x by4\relax%
                        \c@pgfmath@counta=2\relax%
                    \fi%
                \else%
                    \ifdim\pgfmath@x<32pt\relax%
                        \ifdim\pgfmath@x<16pt\relax%
                            \divide\pgfmath@x by8\relax%
                            \c@pgfmath@counta=3\relax%
                        \else%
                            \divide\pgfmath@x by16\relax%
                            \c@pgfmath@counta=4\relax%
                        \fi%
                    \else%
                        \ifdim\pgfmath@x<64pt\relax%
                            \divide\pgfmath@x by32\relax%
                            \c@pgfmath@counta=5\relax%
                        \else%
                            \divide\pgfmath@x by64\relax%
                            \c@pgfmath@counta=6\relax%
                        \fi%
                    \fi%
                \fi%
            \else%
                \ifdim\pgfmath@x<2048pt\relax%
                    \ifdim\pgfmath@x<512pt\relax%
                        \ifdim\pgfmath@x<256pt\relax%
                            \divide\pgfmath@x by128\relax%
                            \c@pgfmath@counta=7\relax%
                        \else%
                            \divide\pgfmath@x by256\relax%
                            \c@pgfmath@counta=8\relax%
                        \fi%
                    \else%
                        \ifdim\pgfmath@x<1024pt\relax%
                            \divide\pgfmath@x by512\relax%
                            \c@pgfmath@counta=9\relax%
                        \else%
                            \divide\pgfmath@x by1024\relax%
                            \c@pgfmath@counta=10\relax%
                        \fi%
                    \fi%
                \else%
                    \ifdim\pgfmath@x<8192pt\relax%
                        \ifdim\pgfmath@x<4096pt\relax%
                            \divide\pgfmath@x by2048\relax%
                            \c@pgfmath@counta=11\relax%
                        \else%
                            \divide\pgfmath@x by4096\relax%
                            \c@pgfmath@counta =12\relax%
                        \fi%
                    \else%
                        \divide\pgfmath@x by8192\relax%
                        \c@pgfmath@counta=13\relax%
                    \fi%
                \fi%
            \fi%
        \else%
            \ifdim\pgfmath@x<1pt\relax%
                \ifdim\pgfmath@x>0.0078125pt\relax% 2^-7
                    \ifdim\pgfmath@x>0.125pt\relax% 2^-3
                        \ifdim\pgfmath@x>0.5pt\relax% 2^-1
                            \multiply\pgfmath@x by2\relax%
                            \c@pgfmath@counta=-1\relax%
                        \else%
                            \multiply\pgfmath@x by4\relax%
                            \c@pgfmath@counta=-2\relax%
                        \fi%
                    \else%
                        \ifdim\pgfmath@x>0.03125pt\relax% 2^-5
                            \ifdim\pgfmath@x>0.0625pt\relax%
                                \multiply\pgfmath@x by8\relax%
                                \c@pgfmath@counta=-3\relax%
                            \else%
                                \multiply\pgfmath@x by16\relax%
                                \c@pgfmath@counta=-4\relax%
                            \fi%
                        \else%
                            \ifdim\pgfmath@x>0.015625pt\relax% 2^-6
                                \multiply\pgfmath@x by32\relax%
                                \c@pgfmath@counta=-5\relax%
                            \else%
                                \multiply\pgfmath@x by64\relax%
                                \c@pgfmath@counta=-6\relax%
                            \fi%
                        \fi%
                    \fi%
                \else%
                    \ifdim\pgfmath@x>0.000244140625pt\relax% 2^-11
                        \ifdim\pgfmath@x>0.001953125pt\relax% 2^-9
                            \ifdim\pgfmath@x>0.00390625pt\relax% 2^-8
                                \multiply\pgfmath@x by128\relax%
                                \c@pgfmath@counta=-7\relax%
                            \else%
                                \multiply\pgfmath@x by256\relax%
                                \c@pgfmath@counta=-8\relax%
                            \fi%
                        \else%
                            \ifdim\pgfmath@x>0.0009765625pt\relax% 2^-10
                                \multiply\pgfmath@x by512\relax%
                                \c@pgfmath@counta=-9\relax%
                            \else%
                                \multiply\pgfmath@x by1024\relax%
                                \c@pgfmath@counta=-10\relax%
                            \fi%
                        \fi%
                    \else%
                        \ifdim\pgfmath@x>0.0001220703125pt\relax% 2^13
                            \ifdim\pgfmath@x>0.0002441406256pt\relax% 2^12
                                \multiply\pgfmath@x by2048\relax%
                                \c@pgfmath@counta=-11\relax%
                            \else%
                                \multiply\pgfmath@x by4096\relax%
                                \c@pgfmath@counta=-12\relax%
                            \fi%
                        \else%
                            \multiply\pgfmath@x by8192\relax%
                            \c@pgfmath@counta=-13\relax%
                        \fi%
                    \fi%
                \fi%
            \fi%
        \fi%
        %
        % Use A+(B+(C+(D+(E+F*x)*x)*x)*x)*x
        %
        % where:
        % A = -2.787927935
        % B =  5.047861502
        % C = -3.489886985
        % D =  1.589480044
        % E = -.4025153233
        % F =  0.04300521312
        %
        \edef\pgfmath@temp{\pgfmath@tonumber{\pgfmath@x}}%
        \pgfmath@x=0.04300521312\pgfmath@x%
        \advance\pgfmath@x by-.4025153233pt\relax%
        \pgfmath@x=\pgfmath@temp\pgfmath@x%
        \advance\pgfmath@x by1.589480044pt\relax%
        \pgfmath@x=\pgfmath@temp\pgfmath@x%
        \advance\pgfmath@x by-3.489886985pt\relax%
        \pgfmath@x=\pgfmath@temp\pgfmath@x%
        \advance\pgfmath@x by5.047861502pt\relax%
        \pgfmath@x=\pgfmath@temp\pgfmath@x%
        \advance\pgfmath@x by-2.787927935pt\relax%
        \advance\pgfmath@x by\c@pgfmath@counta pt\relax%
        \pgfmath@x=0.6931471806\pgfmath@x%
        \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

% log2 function.
%
\pgfmathdeclarefunction{log2}{1}{%
    \begingroup%
        \pgfmathln@{#1}%
        \pgfmath@x=\pgfmathresult pt\relax%
        \pgfmath@x=1.442695041\pgfmath@x% 1/ln(2).
        \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

% log10 function
%
\pgfmathdeclarefunction{log10}{1}{%
    \begingroup%
        \pgfmathln@{#1}%
        \pgfmath@x=\pgfmathresult pt\relax%
        \pgfmath@x=0.43429441\pgfmath@x% 1/ln(10).
        \pgfmath@returnone\pgfmath@x%
    \endgroup%
}

% This is needed since \pgfmathlog2 and \pgfmathlog10 are not legal macro names
\expandafter\let\expandafter\pgfmathlogtwo\csname pgfmathlog2\endcsname
\expandafter\let\expandafter\pgfmathlogtwo@\csname pgfmathlog2@\endcsname
\expandafter\let\expandafter\pgfmathlogten\csname pgfmathlog10\endcsname
\expandafter\let\expandafter\pgfmathlogten@\csname pgfmathlog10@\endcsname

% exp function.
%
\pgfmathdeclarefunction{exp}{1}{%
  \begingroup
    \pgfmath@xc=#1pt\relax
    \pgfmath@yc=#1pt\relax
    \ifdim\pgfmath@xc<-9pt
      \pgfmath@x=1sp\relax
    \else
      \ifdim\pgfmath@xc<0pt
        \pgfmath@xc=-\pgfmath@xc
      \fi
      \pgfmath@x=1pt\relax
      \pgfmath@xa=1pt\relax
      \pgfmath@xb=\pgfmath@x
      \pgfmathloop%
        \divide\pgfmath@xa by\pgfmathcounter
        \pgfmath@xa=\pgfmath@tonumber\pgfmath@xc\pgfmath@xa%
        \advance\pgfmath@x by\pgfmath@xa
      \ifdim\pgfmath@x=\pgfmath@xb
      \else
        \pgfmath@xb=\pgfmath@x
      \repeatpgfmathloop%
      \ifdim\pgfmath@yc<0pt
        \pgfmathreciprocal@{\pgfmath@tonumber\pgfmath@x}%
        \pgfmath@x=\pgfmathresult pt\relax
      \fi
    \fi
    \pgfmath@returnone\pgfmath@x%
  \endgroup
}

% sqrt function.
%
\pgfmathdeclarefunction{sqrt}{1}{%
    \begingroup%
        \expandafter\pgfmath@x#1pt\relax%
        \ifdim\pgfmath@x<0pt\relax%
            \pgfmath@error{I cannot calculate the square-root of the negative number `#1'}{}%
        \else%
            \ifdim\pgfmath@x<10pt\relax%
                \def\pgfmath@zeros{0}%
                \def\pgfmath@targetiterations{1}%
            \else%
                \ifdim\pgfmath@x<100pt\relax%
                    \def\pgfmath@zeros{}%
                    \def\pgfmath@targetiterations{1}%
                \else%
                    \ifdim\pgfmath@x<1000pt\relax%
                        \def\pgfmath@zeros{0}%
                        \def\pgfmath@targetiterations{2}%
                    \else%
                        \ifdim\pgfmath@x<10000pt\relax%
                            \def\pgfmath@zeros{}%
                            \def\pgfmath@targetiterations{2}%
                    \else%
                            \def\pgfmath@zeros{0}%
                            \def\pgfmath@targetiterations{3}%
        \fi\fi\fi\fi\fi%
        \edef\pgfmath@temp{\pgfmath@zeros\pgfmath@tonumber{\pgfmath@x}}%
        \expandafter\pgfmath@sqrt@\pgfmath@temp\pgfmath@%
}
\def\pgfmath@sqrt@#1.#2\pgfmath@{\pgfmath@@sqrt@#1#2\pgfmath@empty\pgfmath@empty\pgfmath@}

\def\pgfmath@@sqrt@#1#2{%
        \c@pgfmath@countb=#1#2\relax%
        \ifnum\c@pgfmath@countb>35\relax%
            \ifnum\c@pgfmath@countb>63\relax%
                \ifnum\c@pgfmath@countb>80\relax%
                    \c@pgfmath@counta=9\relax%
                \else%
                    \c@pgfmath@counta=8\relax%
                \fi%
            \else%
                \ifnum\c@pgfmath@countb>48\relax%
                    \c@pgfmath@counta=7\relax%
                \else%
                    \c@pgfmath@counta=6\relax%
                \fi%
            \fi%
        \else%
            \ifnum\c@pgfmath@countb>15\relax%
                \ifnum\c@pgfmath@countb>24\relax%
                    \c@pgfmath@counta5\relax%
                \else%
                    \c@pgfmath@counta=4\relax%
                \fi%
            \else%
                \ifnum\c@pgfmath@countb>3\relax%
                    \ifnum\c@pgfmath@countb>8\relax%
                        \c@pgfmath@counta=3\relax%
                    \else%
                        \c@pgfmath@counta=2\relax%
                    \fi%
                \else%
                    \ifnum\c@pgfmath@countb>0\relax%
                        \c@pgfmath@counta=1\relax%
                    \else%
                        \c@pgfmath@counta=0\relax%
                    \fi%
                \fi%
            \fi%
        \fi%
        \edef\pgfmath@root{\the\c@pgfmath@counta}%
        \edef\pgfmath@rootspecial{\the\c@pgfmath@counta}%
        \multiply\c@pgfmath@counta by-\c@pgfmath@counta\relax%
        \advance\c@pgfmath@counta by#1#2\relax%
        \edef\pgfmath@remainder{\the\c@pgfmath@counta}%
        \pgfmath@@@sqrt@%
}

\def\pgfmath@@@sqrt@#1#2{%
        \ifx\pgfmath@empty#1%
            \edef\pgfmath@remainder{\pgfmath@remainder00}%
            \def\pgfmath@tokens{\pgfmath@empty\pgfmath@empty}%
        \else%
            \ifx\pgfmath@empty#2%
                \edef\pgfmath@remainder{\pgfmath@remainder#10}%
                \def\pgfmath@tokens{\pgfmath@empty\pgfmath@empty}%
            \else%
                \edef\pgfmath@remainder{\pgfmath@remainder#1#2}%
                \def\pgfmath@tokens{}%
        \fi\fi%
        \c@pgfmath@counta=\pgfmath@rootspecial\relax%
        \multiply\c@pgfmath@counta by20\relax%
        \c@pgfmath@countb=\c@pgfmath@counta%
        \multiply\c@pgfmath@countb by6\relax%
        \advance\c@pgfmath@countb by36\relax%
        \c@pgfmath@countc=\c@pgfmath@counta%
        \multiply\c@pgfmath@countc by2\relax%
        \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
            \advance\c@pgfmath@countb by-\c@pgfmath@countc%
            \advance\c@pgfmath@countb by-20\relax%
            \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                \advance\c@pgfmath@countb by-\c@pgfmath@countc%
                \advance\c@pgfmath@countb by-12\relax%
                \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                    \advance\c@pgfmath@countb by-\c@pgfmath@counta%
                    \advance\c@pgfmath@countb by-3\relax%
                    \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                        \def\pgfmath@digit{0}%
                    \else%
                        \def\pgfmath@digit{1}%
                    \fi%
                \else%
                    \advance\c@pgfmath@countb by\c@pgfmath@counta%
                    \advance\c@pgfmath@countb by5\relax%
                    \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                        \def\pgfmath@digit{2}%
                    \else%
                        \def\pgfmath@digit{3}%
                    \fi%
                \fi%
            \else%
                \advance\c@pgfmath@countb by\c@pgfmath@counta%
                \advance\c@pgfmath@countb by9\relax%
                \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                    \def\pgfmath@digit{4}%
                \else%
                    \def\pgfmath@digit{5}%
                \fi%
            \fi%
        \else%
            \advance\c@pgfmath@countb by\c@pgfmath@countc%
            \advance\c@pgfmath@countb by28\relax%
            \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                \advance\c@pgfmath@countb by-\c@pgfmath@counta%
                \advance\c@pgfmath@countb by-15\relax%
                \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                    \def\pgfmath@digit{6}%
                \else%
                    \def\pgfmath@digit{7}%
                \fi%
            \else%
                \advance\c@pgfmath@countb by\c@pgfmath@counta%
                \advance\c@pgfmath@countb by17\relax%
                \ifnum\c@pgfmath@countb>\pgfmath@remainder\relax%
                    \def\pgfmath@digit{8}%
                \else%
                    \def\pgfmath@digit{9}%
                \fi%
            \fi%
        \fi%
        \edef\pgfmath@rootspecial{\pgfmath@rootspecial\pgfmath@digit}%
        \advance\c@pgfmath@counta by\pgfmath@digit\relax%
        \multiply\c@pgfmath@counta by-\pgfmath@digit\relax%
        \advance\c@pgfmath@counta by\pgfmath@remainder\relax%
        \edef\pgfmath@remainder{\the\c@pgfmath@counta}%
        \c@pgfmath@counta=\pgfmath@targetiterations\relax%
        \advance\c@pgfmath@counta by-1\relax%
        \edef\pgfmath@targetiterations{\the\c@pgfmath@counta}%
        \ifnum\c@pgfmath@counta=0\relax%
            \edef\pgfmath@root{\pgfmath@root.\pgfmath@digit}%
        \else%
            \edef\pgfmath@root{\pgfmath@root\pgfmath@digit}%
        \fi%
        \ifnum\c@pgfmath@counta=-4\relax% -n+1 digits of precision.
            \let\pgfmath@next\pgfmath@sqrt@end%
        \else%
            \let\pgfmath@next\pgfmath@@@sqrt@%
        \fi%
        \expandafter\pgfmath@next\pgfmath@tokens%
}

\def\pgfmath@sqrt@end#1\pgfmath@{%
        \edef\pgfmathresult{\pgfmath@root}%
        \pgfmath@smuggleone\pgfmathresult%
    \endgroup}

% \pgfmathpow
%
% Calculates #1 ^ #2
%
\pgfmathdeclarefunction{pow}{2}{%
  \begingroup%
    \pgfmath@xa=#1pt%
    \pgfmath@xb=#2pt%
    \ifdim\pgfmath@xa=0pt\relax%
      \ifdim\pgfmath@xb=0pt\relax%
        \pgfmath@x=1pt\relax%
      \else%
        \pgfmath@x=0pt\relax%
      \fi%
    \else%
      \afterassignment\pgfmath@x%
      \expandafter\c@pgfmath@counta\the\pgfmath@xb\relax%
      \ifnum\c@pgfmath@counta<0\relax%
        \c@pgfmath@counta=-\c@pgfmath@counta%
        \pgfmathreciprocal@{#1}%
        \pgfmath@xa=\pgfmathresult pt\relax%
      \fi
      \ifdim\pgfmath@x=0pt\relax%
        \pgfmath@x=1pt\relax%
        \pgfmathloop%
          \ifnum\c@pgfmath@counta>0\relax%
            \ifodd\c@pgfmath@counta%
              \pgfmath@x=\pgfmath@tonumber{\pgfmath@x}\pgfmath@xa%
            \fi
            \ifnum\c@pgfmath@counta>1\relax%
              \pgfmath@xa=\pgfmath@tonumber{\pgfmath@xa}\pgfmath@xa%
            \fi%
            \divide\c@pgfmath@counta by2\relax%
        \repeatpgfmathloop%
      \else%
        \pgfmathln@{#1}%
        \pgfmath@x=\pgfmathresult pt\relax%
        \pgfmath@x=\pgfmath@tonumber{\pgfmath@xb}\pgfmath@x%
        \pgfmathexp@{\pgfmath@tonumber{\pgfmath@x}}%
        \pgfmath@x=\pgfmathresult pt\relax%
      \fi%
    \fi
    \pgfmath@returnone\pgf@x%
  \endgroup%
}

% factorial function.
%
\pgfmathdeclarefunction{factorial}{1}{%
    \begingroup%
        \afterassignment\pgfmath@gobbletilpgfmath@%
        \c@pgfmath@counta=#1\relax\pgfmath@%
        \pgfmath@x=1pt\relax%
        \pgfmathloop%
        \ifnum\c@pgfmath@counta<2\relax%
        \else%
            \multiply\pgfmath@x by\c@pgfmath@counta%
            \advance\c@pgfmath@counta by-1\relax%
        \repeatpgfmathloop%
        \edef\pgfmathresult{\pgfmath@tonumber{\pgfmath@x}}%
        \pgfmath@smuggleone\pgfmathresult%
    \endgroup%
}

% Local Variables:
% coding: undecided-unix
% End:
