Add type estimation to rendercharts.js to improve CSV portability

1 files changed, 58 insertions, 3 deletions

diff --git a/js/rendercharts.js b/js/rendercharts.js
index 24bce90..aaa3ffb 100644
--- a/js/rendercharts.js
+++ b/js/rendercharts.js
@@ -1,13 +1,21 @@
 (function(window, document) {

   // http://stackoverflow.com/a/1414175/2132223

-  var stringToBoolean = function (str) {

+  var stringToBoolean1 = function (str) {

     switch(str.toLowerCase()) {

       case "true": case "yes": case "1": return true;

       case "false": case "no": case "0": case null: return false;

-      default: return Boolean(str);

+      default: return null;

     }

   };

 

+  var stringToBoolean = function (str) {

+    var b = stringToBoolean1(str);

+    if(b === null) {

+      b = Boolean(str);

+    }

+    return b;

+  };

+

   // http://stackoverflow.com/a/4981700/2132223

   var getNestedObjectByName = function (strObjName) {

     var parts = strObjName.split(".");

@@ -109,6 +117,40 @@
   };

   // end of http://code.google.com/p/csv-to-array/

 

+  var estimateColumnType = function (csvAsArray, columnIndex) {

+    var isColumnBoolean = function (csvAsArray, columnIndex) {

+      for(var row = 0, nRow = csvAsArray.length; row < nRow; ++row) {

+        if(stringToBoolean1(csvAsArray[row][columnIndex]) === null) {

+          return false;

+        }

+      }

+      return true;

+    };

+

+    var isColumnNumber = function (csvAsArray, columnIndex) {

+      // http://stackoverflow.com/a/1830844/2132223

+      var isNumber = function(n) {

+        return !isNaN(parseFloat(n)) && isFinite(n);

+      }

+      for(var row = 0, nRow = csvAsArray.length; row < nRow; ++row) {

+        if(! isNumber(csvAsArray[row][columnIndex])) {

+          return false;

+        }

+      }

+      return true;

+    };

+

+    if(isColumnBoolean(csvAsArray, columnIndex)) {

+      return "boolean";

+    }

+

+    if(isColumnNumber(csvAsArray, columnIndex)) {

+      return "number";

+    }

+

+    return "string";

+  };

+

   var drawTable = function (gvCtor, gvOptions, csvUrl, csvEl) {

     var r = new XMLHttpRequest();

     r.open("GET", csvUrl, true);

@@ -119,6 +161,7 @@
         var gvdt = new google.visualization.DataTable()

         var csvHeaderLine = csvAsArray.shift();

         for(var i = 0; i < csvHeaderLine.length; i++) {

+/*

           var csvHeaderElement = csvHeaderLine[i].split(":");

           var csvHeaderName = "?";

           var csvHeaderType = "string";

@@ -137,7 +180,19 @@
               case "boolean": csvAsArray[j][i] = stringToBoolean(csvAsArray[j][i]); break;

             }

           }

-        }

+*/

+			var csvHeaderType = estimateColumnType(csvAsArray, i);

+//			alert("column" + i + " = " + csvHeaderType);

+          gvdt.addColumn(csvHeaderType, csvHeaderLine[i]);

+          for(var j = 0; j < csvAsArray.length; j++) {

+            switch(csvHeaderType) {

+              default:

+              case "string":  csvAsArray[j][i] = String(csvAsArray[j][i]); break;

+              case "number":  csvAsArray[j][i] = Number(csvAsArray[j][i]); break;

+              case "boolean": csvAsArray[j][i] = stringToBoolean(csvAsArray[j][i]); break;

+            }

+          }

+		}

         gvdt.addRows(csvAsArray);

         var ctor = getNestedObjectByName(gvCtor);

         var table = new ctor (csvEl);