Allow negative dimensions for \\[] but clip to 0 since this isn't really allowed in MathML. I will need to figure out something better for the future, but for now this will prevent the error message. Issue #236.

Author: dpvc

unpacked/extensions/TeX/AMSmath.js

@@ -22,7 +22,7 @@
  */
 
 MathJax.Extension["TeX/AMSmath"] = {
-  version: "2.0.2",
+  version: "2.0.3",
 
   number: 0,        // current equation number
   startNumber: 0,   // current starting equation number (for when equation is restarted)
@@ -41,7 +41,12 @@ MathJax.Hub.Register.StartupHook("TeX Jax Ready",function () {
       STACKITEM = TEX.Stack.Item,
       CONFIG = TEX.config.equationNumbers;
 
-  var COLS = function (W) {return W.join("em ") + "em"};
+  var COLS = function (W) {
+    var WW = [];
+    for (var i = 0, m = W.length; i < m; i++) 
+      {WW[i] = TEX.Parse.prototype.Em(W[i])}
+    return WW.join(" ");
+  };
 
   /******************************************************************************/
 

unpacked/jax/input/TeX/config.js

@@ -24,7 +24,7 @@
 
 MathJax.InputJax.TeX = MathJax.InputJax({
   id: "TeX",
-  version: "2.0.6",
+  version: "2.0.7",
   directory: MathJax.InputJax.directory + "/TeX",
   extensionDir: MathJax.InputJax.extensionDir + "/TeX",
 

unpacked/jax/input/TeX/jax.js

@@ -296,7 +296,7 @@
       }
       if (this.rowspacing) {
         var rows = this.arraydef.rowspacing.split(/ /);
-        while (rows.length < this.table.length) {rows.push(this.rowspacing)}
+        while (rows.length < this.table.length) {rows.push(this.rowspacing+"em")}
         this.arraydef.rowspacing = rows.join(' ');
       }
     },
@@ -1613,7 +1613,7 @@
       var n;
       if (this.string.charAt(this.i) === "[") {
         n = this.GetBrackets(name,"").replace(/ /g,"");
-        if (n && !n.match(/^(((\.\d+|\d+(\.\d*)?))(pt|em|ex|mu|mm|cm|in|pc))$/))
+        if (n && !n.match(/^((-?(\.\d+|\d+(\.\d*)?))(pt|em|ex|mu|mm|cm|in|pc))$/))
           {TEX.Error("Bracket argument to "+name+" must be a dimension")}
       }
       this.Push(STACKITEM.cell().With({isCR: true, name: name, linebreak: true}));
@@ -1622,8 +1622,8 @@
         if (n && top.arraydef.rowspacing) {
           var rows = top.arraydef.rowspacing.split(/ /);
           if (!top.rowspacing) {top.rowspacing = this.dimen2em(rows[0])}
-          while (rows.length < top.table.length) {rows.push(top.rowspacing)}
-          rows[top.table.length-1] = (top.rowspacing+this.dimen2em(n)) + "em";
+          while (rows.length < top.table.length) {rows.push(this.Em(top.rowspacing))}
+          rows[top.table.length-1] = this.Em(Math.max(0,top.rowspacing+this.dimen2em(n)));
           top.arraydef.rowspacing = rows.join(' ');
         }
       } else {
@@ -1633,7 +1633,7 @@
     },
     emPerInch: 7.2,
     dimen2em: function (dim) {
-      var match = dim.match(/^((?:\.\d+|\d+(?:\.\d*)?))(pt|em|ex|mu|pc|in|mm|cm)/);
+      var match = dim.match(/^(-?(?:\.\d+|\d+(?:\.\d*)?))(pt|em|ex|mu|pc|in|mm|cm)/);
       var m = parseFloat(match[1]||"1"), unit = match[2];
       if (unit === "em") {return m}
       if (unit === "ex") {return m * .43}
@@ -1645,6 +1645,10 @@
       if (unit === "mu") {return m / 18}
       return 0;
     },
+    Em: function (m) {
+      if (Math.abs(m) < .0006) {return "0em"}
+      return m.toFixed(3).replace(/\.?0+$/,"") + "em";
+    },
 
     HLine: function (name,style) {
       if (style == null) {style = "solid"}