--- loncom/xml/algebra/AlgParser.pm	2005/02/24 01:21:51	1.1
+++ loncom/xml/algebra/AlgParser.pm	2005/02/24 08:34:52	1.8
@@ -6,11 +6,12 @@
 ## Additions and modifications were made by Arnold Pizer, Dept of Math, Univ of Rochester
 
 #use Data::Dumper;
+use strict;
 
 package AlgParser;
 use HTML::Entities;
 
-%close = ();
+my %close = ();
 
 sub new {
   my $package = shift;
@@ -36,30 +37,34 @@ $close{'{'} = '}';
 $close{'['} = ']';
 $close{'('} = ')';
 
-$binoper3 = '(?:\\^|\\*\\*)';
-$binoper2 = '[/*_,]';
-$binoper1 = '[-+=><%!#]';
-$openparen = '[{(\\[]';
-$closeparen = '[})\\]]';
-$varname = '[A-Za-z](?:_[0-9]+)?';
-$specialvalue = '(?:e|pi|da|db|dc|de|df|dg|dh|di|dj|dk|dl|dm|dn|do|dp|dq|dr|ds|dt|du|dv|dw|dx|dy|dz|infty|alpha|bita|gamma|zita|thita|iota|kappa|lambda|mu|nu|xi|rho|sigma|tau|phi|chi|psi|omega|zepslon|zdelta|xeta|zupslon|zeroplace)';
-$numberplain = '(?:\d+(?:\.\d*)?|\.\d+)';
-$numberE = '(?:' . $numberplain . 'E[-+]?\d+)';
-$number = '(?:' . $numberE . '|' . $numberplain . ')';
+my $binoper3 = '(?:\\^|\\*\\*)';
+my $binoper2 = '[/*_,]';
+my $binoper1 = '[-+=><%!#]';
+my $openparen = '[{(\\[]';
+my $closeparen = '[})\\]]';
+my $varname = '[A-Za-z](?:_[0-9]+)?';
+my $greek='alpha|(?:(?:(?:var)?(?:[tT]h))|(?:[bz])?)eta|[gG]amma|iota|kappa|[lL]ambda|mu|nu|[xX]i|(?:var)?rho|(?:var)?[sS]igma|tau|(?:var)?(?:[pP])hi|chi|[oO]mega|(?:(?:var)?(?:[eE])|(?:[uU]))psilon|[dD]elta|[pP]si|(?:var)?[pP]i';
+my $delete='zeroplace';
+my $escape='infty';
+my $specialvalue = '(?:'.$escape.'|'.$greek.'|'.$delete.'|d[a-z]|e)';
+
+my $numberplain = '(?:\d+(?:\.\d*)?|\.\d+)';
+my $numberE = '(?:' . $numberplain . 'E[-+]?\d+)';
+my $number = '(?:' . $numberE . '|' . $numberplain . ')';
 #
 #  DPVC -- 2003/03/31
 #       added missing trig and inverse functions
 #
 #$trigfname = '(?:cosh|sinh|tanh|cot|(?:a(?:rc)?)?cos|(?:a(?:rc)?)?sin|' .
 #    '(?:a(?:rc)?)?tan|sech?)';
-$trigfname = '(?:(?:a(?:rc)?)?(?:sin|cos|tan|sec|csc|cot)h?)';
+my $trigfname = '(?:(?:a(?:rc)?)?(?:sin|cos|tan|sec|csc|cot)h?)';
 #
 #  End DPVC
 #
-$otherfunc = '(?:exp|abs|logten|log|ln|sqrt|sgn|step|fact|int|lim|fun[a-zA-Z])';
-$funcname = '(?:' . $otherfunc . '|' . $trigfname . ')';
+my $otherfunc = '(?:exp|abs|logten|log|ln|sqrt|sgn|step|fact|int|lim|fun[a-zA-Z])';
+my $funcname = '(?:' . $otherfunc . '|' . $trigfname . ')';
 
-$tokenregexp = "(?:($binoper3)|($binoper2)|($binoper1)|($openparen)|" .
+my $tokenregexp = "(?:($binoper3)|($binoper2)|($binoper1)|($openparen)|" .
     "($closeparen)|($funcname)|($specialvalue)|($varname)|" .
     "($numberE)|($number))";
 
@@ -95,7 +100,7 @@ sub parse {
   my (@pushback) = ();
 
   my $currentref = \$self->{parseresult}->[1];
-  my $curenttok;
+  my $currenttok;
 
   my $sstring = shift;
   $self->inittokenizer($sstring);
@@ -383,7 +388,9 @@ sub normalize_expr {
 }
 
 package AlgParserWithImplicitExpand;
+no strict;
 @ISA=qw(AlgParser);
+use strict;
 
 sub arraytoexpr {
   my ($self) = shift;
@@ -558,6 +565,11 @@ sub tolatex {
 	return('\frac{' . $args[1]->tolatex() . '}'.
                '{' . $args[2]->tolatex() . '}' ); 
     }
+    elsif ($args[0] eq '*'){
+#	return('\frac{' . $p1 . $args[1]->tolatex() . $p2 . '}'.
+#               '{' . $p3 . $args[2]->tolatex() . $p4 . '}' );
+	return($args[1]->tolatex() . '\cdot ' . $args[2]->tolatex() ); 
+    }
     else{
     return ($p1 . $args[1]->tolatex() . $p2 . $args[0] . $p3 .
             $args[2]->tolatex() . $p4);
@@ -582,20 +594,30 @@ sub tolatex {
       #       added missing trig functions
       #
       #$specialfunc = '(?:abs|logten|asin|acos|atan|sech|sgn|step|fact)';
-      $specialfunc = '(?:abs|logten|a(?:sin|cos|tan|sec|csc|cot)h?|sgn|step|fact)';
+      my $specialfunc = '(?:abs|(logten)|a(sin|cos|tan|sec|csc|cot)(h)?|sgn|step|fact)';
       #
       #  End DPVC
       #
 
       if ($args[0] =~ /$specialfunc/) {
-         return ('\mbox{' . $args[0] .'}'. $p1 . $args[1]->tolatex() . $p2);
+	  if (defined($1)) {
+	      return ('\mbox{log}_{10}'. $p1 . $args[1]->tolatex() . $p2);
+	  }
+	  elsif (defined($2)) {
+	      return ('\mbox{' . $2.$3 .'}^{-1}'. $p1 . $args[1]->tolatex() . $p2);
+	  }
+	  else {
+	      return ('\mbox{' . $args[0] .'}'. $p1 . $args[1]->tolatex() . $p2);
+	  }
       }
       else {
         return ('\\' . $args[0] . $p1 . $args[1]->tolatex() . $p2);
       }
   };
   /special/ && do {
-    if ($args[0] eq 'pi') {return '\pi';} else {return $args[0];}
+      if    ($args[0] =~/($greek|$escape)/) {return '\\'.$1;}
+      elsif ($args[0] =~/$delete/) {return '';}
+      else { return $args[0]; }
   };
   /varname|(:?number$)/ && return $args[0];
   /numberE/ && do {
@@ -628,8 +650,9 @@ sub fromarray {
 }
 
 package ExprWithImplicitExpand;
+no strict;
 @ISA=qw(Expr);
-
+use strict;
 
 sub tostring {
 # print STDERR "ExprWIE::tostring\n";