--- loncom/xml/londefdef.pm	2015/03/09 19:05:33	1.456
+++ loncom/xml/londefdef.pm	2016/08/10 00:29:06	1.456.2.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Tags Default Definition Module 
 #
-# $Id: londefdef.pm,v 1.456 2015/03/09 19:05:33 raeburn Exp $
+# $Id: londefdef.pm,v 1.456.2.1 2016/08/10 00:29:06 raeburn Exp $
 # 
 #
 # Copyright Michigan State University Board of Trustees
@@ -2063,8 +2063,8 @@ sub end_dt {
 
 sub item_cleanup {
     my $item=&Apache::lonxml::endredirection();
-    $item=~s/\\begin{center}//g;
-    $item=~s/\\end{center}//g;
+    $item=~s/\\begin\{center}//g;
+    $item=~s/\\end\{center}//g;
     return $item;
 }
 
@@ -4440,17 +4440,17 @@ sub LATEX_length {
     $garbage=~s/^\s+(\S.*)/$1/;#space before 
     $garbage=~s/(.*\S)\s+$/$1/;#space after 
     $garbage=~s/(\s)+/$1/;#only one space
-    $garbage=~s/(\\begin{([^\}]+)}|\\end{([^\}]+)})//g;#remove LaTeX \begin{...} and \end{...}
-    $garbage=~s/(\$\_\{|\$\_|\$\^{|\$\^|\}\$)//g;#remove $_{,$_,$^{,$^,}$
+    $garbage=~s/(\\begin\{([^\}]+)}|\\end\{([^\}]+)})//g;#remove LaTeX \begin{...} and \end{...}
+    $garbage=~s/(\$\_\{|\$\_|\$\^\{|\$\^|\}\$)//g;#remove $_{,$_,$^{,$^,}$
     $garbage=~s/([^\\])\$/$1/g;#$
-    $garbage=~s/(\\ensuremath\{\_\{|\\ensuremath\{\_|\\ensuremath\{\^{|\\ensuremath\{\^|\})//g;#remove \ensuremath{...}
+    $garbage=~s/(\\ensuremath\{\_\{|\\ensuremath\{\_|\\ensuremath\{\^\{|\\ensuremath\{\^|\})//g;#remove \ensuremath{...}
    $garbage=~s/(\\alpha|\\beta|\\gamma|\\delta|\\epsilon|\\verepsilon|\\zeta|\\eta|\\theta|\\vartheta|\\iota|\\kappa|\\lambda|\\mu|\\nu|\\xi|\\pi|\\varpi|\\rho|\\varrho|\\sigma|\\varsigma|\\tau|\\upsilon|\\phi|\\varphi|\\chi|\\psi|\\omega|\\Gamma|\\Delta|\\Theta|\\Lambda|\\Xi|\\Pi|\\Sigma|\\Upsilon|\\Phi|\\Psi|\\Omega)/1/g;
     $garbage=~s/(\\pm|\\mp|\\times|\\div|\\cdot|\\ast|\\star|\\dagger|\\ddagger|\\amalg|\\cap|\\cup|\\uplus|\\sqcap|\\sqcup|\\vee|\\wedge|\\oplus|\\ominus|\\otimes|\\circ|\\bullet|\\diamond|\\lhd|\\rhd|\\unlhd|\\unrhd|\\oslash|\\odot|\\bigcirc|\\Box|\\Diamond|\\bigtriangleup|\\bigtriangledown|\\triangleleft|\\triangleright|\\setminus|\\wr)/1/g;
     $garbage=~s/(\\le|\\ll|\\leq|\\ge|\\geq|\\gg|\\neq|\\doreq|\\sim|\\simeq|\\subset|\\subseteq|\\sqsubset|\\sqsubseteq|\\in|\\vdash|\\models|\\supset|\\supseteq|\\sqsupset|\\sqsupseteq|\\ni|\\dash|\\perp|\\approx|\\cong|\\equiv|\\propto|\\prec|\\preceq|\\parallel|\\asymp|\\smile|\\frown|\\bowtie|\\succ|\\succeq|\\mid)/1/g;
     $garbage=~s/(\\not<|\\\\not\\le|\\not\\prec|\\not\\preceq|\\not\\subset|\\not\\subseteq|\\not\\sqsubseteq|\\not\\in|\\not>|\\not\\ge|\\not\\succ|\\notsucceq|\\not\\supset|\\notsupseteq|\\not\\sqsupseteq|\\notin|\\not=|\\not\\equiv|\\not\\sim|\\not\\simeq|\\not\\approx|\\not\\cong|\\not\\asymp)/1/g;
     $garbage=~s/(\\leftarrow|\\gets|\\Leftarrow|\\rightarrow|\\to|\\Rightarrow|\\leftrightarrow|\\Leftrightarrow|\\mapsto|\\hookleftarrow|\\leftharpoonup|\\leftkarpoondown|\\rightleftharpoons|\\longleftarrow|\\Longleftarrow|\\longrightarrow|\\Longrightarrow|\\longleftrightarrow|\\Longleftrightarrow|\\longmapsto|\\hookrightarrow|\\rightharpoonup|\\rightharpoondown|\\uparrow|\\Uparrow|\\downarrow|\\Downarrow|\\updownarrow|\\Updownarrow|\\nearrow|\\searrow|\\swarrow|\\nwarrow)/11/g;
     $garbage=~s/(\\aleph|\\hbar|\\imath|\\jmath|\\ell|\\wp|\\Re|\\Im|\\mho|\\prime|\\emptyset|\\nabla|\\surd|\\partial|\\top|\\bot|\\vdash|\\dashv|\\forall|\\exists|\\neg|\\flat|\\natural|\\sharp|\\\||\\angle|\\backslash|\\Box|\\Diamond|\\triangle|\\clubsuit|\\diamondsuit|\\heartsuit|\\spadesuit|\\Join|\\infty)/11/g;
-    $garbage=~s/(\\hat{([^}]+)}|\\check{([^}]+)}|\\dot{([^}]+)}|\\breve{([^}]+)}|\\acute{([^}]+)}|\\ddot{([^}]+)}|\\grave{([^}]+)}|\\tilde{([^}]+)}|\\mathring{([^}]+)}|\\bar{([^}]+)}|\\vec{([^}]+)})/$1/g;
+    $garbage=~s/(\\hat\{([^}]+)}|\\check\{([^}]+)}|\\dot\{([^}]+)}|\\breve\{([^}]+)}|\\acute\{([^}]+)}|\\ddot\{([^}]+)}|\\grave\{([^}]+)}|\\tilde\{([^}]+)}|\\mathring\{([^}]+)}|\\bar\{([^}]+)}|\\vec\{([^}]+)})/$1/g;
     #remove some other LaTeX command
     $garbage=~s|\\(\w+)\\|\\|g;	 
     $garbage=~s|\\(\w+)(\s*)|$2|g;