say
say $wThe following external files are available:
say
say   $rDEMO$c         Demonstration file of computations with CLICAL.
say   $rSPINOR$c       Dirac, Majorana and Weyl/Pure spinors of $wR^3,1$c.
say   $rEXTERIOR$c     Functions with variables in the exterior algebra.
say   $rOCTONION$c     Cayley algebra of octonions in $wR+R7 (= R+R^0,7)$c.
say   $rTRALITY$c      Cartan's triality automorphism of $wSpin(8)$c in $yCl 8$c.
say   $rCONFORM$c      Conformal transformations and Vahlen matrices.
say
say $wYou can call in the above external files by typing:
say
say $w> $yGET DEMO
say $w> $yGET SPINOR
say $w> $yGET EXTERIOR
say $w> $yGET OCTONION
say $w> $yGET TRIALITY
say $w> $yGET CONFORM
say
say For an elementary introduction to CLICAL, type $yTUTOR$c.
say $mTo continue with this $yGUIDE$c$m, press <CARRIAGE RETURN> or <ENTER>$c.
pause
say You can create external files of your own.
say To do this, you must first quit CLICAL.
say Then write your own external file using a text processor.
say An external file contains a sequence of command lines for CLICAL,
Say with comment lines which begin with the word $ySAY$c.
say
say $rFor instance, an external file with the content:
say   $gecho -
say   $gdimension 2
say   $gecho +
say   $gsay Compute  exp(i pi)
say   $gexp(i pi)
say $rresults in the following output:
say
echo -
dimension 2
echo +
say Compute  exp(i pi)
exp(i pi)
say
say $mPress <CARRIAGE RETURN>.
pause
say $wSAMPLE EXTERNAL FILES FOR PHYSICAL EQUATIONS AND DIFFERENTIAL FORMS:
say
say To explore the derivative/differential operator $wD$c acting on solutions of 
say the Maxwell and Dirac equations and on some sample functions and forms,
say type $yGET DERIVE4.CLI$c, $yGET MAXWELL.CLI$c, $yGET DIRAC31.CLI$c, $yGET FUNCT31.CLI$c and
say $yGET FORMS31.CLI$c.  Try conformal and linear transformations of the equations
say with $yCONFEX31.CLI$c and $yLINEAR4.CLI$c.
say
say
say $wHOW TO DISPLAY COLORS:
say 
say If you have a color monitor and a color card, you can write colored files.
say Type $yQUIT$c to exit CLICAL and see the content of this file called GUIDE
say to see how the following colors are produced:
say
say                          $bBlue
say                       $cCyan  $mMagenta
say                          $wWhite
say                   $gGreen  $yYellow  $rRed
say
say $mEnd of the external file GUIDE.
