--- loncom/xml/algebra/AlgParser.pm	2005/02/24 06:21:10	1.2
+++ loncom/xml/algebra/AlgParser.pm	2005/02/24 08:25:21	1.4
@@ -43,7 +43,10 @@ my $binoper1 = '[-+=><%!#]';
 my $openparen = '[{(\\[]';
 my $closeparen = '[})\\]]';
 my $varname = '[A-Za-z](?:_[0-9]+)?';
-my $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)';
+my $greek='alpha|bita|gamma|zita|thita|iota|kappa|lambda|mu|nu|xi|rho|sigma|tau|phi|chi|psi|omega|zepslon|zdelta|xeta|zupslon';
+my $delete='zeroplace';
+my $escape='infty';
+my $specialvalue = '(?:e|pi|d[a-z]|'.$escape.'|'.$greek.'|'.$delete.')';
 my $numberplain = '(?:\d+(?:\.\d*)?|\.\d+)';
 my $numberE = '(?:' . $numberplain . 'E[-+]?\d+)';
 my $number = '(?:' . $numberE . '|' . $numberplain . ')';