implemented size validation in method size

src/function/matrix/eye.js

@@ -36,7 +36,6 @@ function eye (m, n) {
         }
     }
 
-    // TODO: add support for n dimensional matrices
     // TODO: use zeros(m, n) instead, then fill the diagonal with ones
     var res = [];
     for (var r = 0; r < rows; r++) {
@@ -47,6 +46,7 @@ function eye (m, n) {
         res[r] = row;
     }
 
+    // fill in ones on the diagonal
     var min = Math.min(rows, cols);
     for (var d = 0; d < min; d++) {
         res[d][d] = 1;
@@ -55,7 +55,8 @@ function eye (m, n) {
     return res;
 }
 
-math.eye = eye;
+// TODO: export method eye to math
+// math.eye = eye;
 
 /**
  * Function documentation

src/function/matrix/size.js

@@ -25,6 +25,8 @@ function size (x) {
     }
 
     if (x instanceof Array) {
+        var s = getSize(x);
+        validate(x, s);
         return [getSize(x)];
     }
     // TODO: implement matrix support
@@ -41,11 +43,8 @@ function getSize (x) {
     if (x instanceof Array) {
         var sizeX = x.length;
         if (sizeX) {
-            var sizeI = getSize(x[0]);
-
-            // TODO: validate whether the other elements have the same size
-
-            return [sizeX].concat(sizeI);
+            var size0 = getSize(x[0]);
+            return [sizeX].concat(size0);
         }
         else {
             return [sizeX];
@@ -56,7 +55,73 @@ function getSize (x) {
     }
 }
 
-math.size = size;
+/**
+ * Verify whether each element in an n dimensional array has the correct size
+ * @param {Array | Object} array    Array to be validated
+ * @param {Number[]} size           Array with dimensions
+ * @param {Number} [dim]            Current dimension
+ * @throw Error
+ */
+function validate(array, size, dim) {
+    var i,
+        len = array.length;
+    if (!dim) {
+        dim = 0;
+    }
+
+    if (len != size[dim]) {
+        throw new Error('Dimension mismatch (' + len + ' != ' + size[dim] + ')');
+    }
+
+    if (dim < size.length - 1) {
+        // recursively validate each child array
+        var dimNext = dim + 1;
+        for (i = 0; i < len; i++) {
+            var child = array[i];
+            if (!(child instanceof Array)) {
+                throw new Error('Dimension mismatch ' +
+                    '(' + (size.length - 1) + ' < ' + size.length + ')');
+            }
+            validate(array[i], size, dimNext);
+        }
+    }
+    else {
+        // last dimension. none of the childs may be an array
+        for (i = 0; i < len; i++) {
+            if (array[i] instanceof Array) {
+                throw new Error('Dimension mismatch ' +
+                    '(' + (size.length + 1) + ' > ' + size.length + ')');
+            }
+        }
+    }
+
+    return true;
+}
+
+/**
+ * Compare two arrays
+ * @param a
+ * @param b
+ * @return {Boolean} equal   True if both arrays are equal, else false
+ */
+function compare(a, b) {
+    var len = a.length;
+    if (len != b.length) {
+        return false;
+    }
+
+    for (var i = 0; i < len; i++) {
+        if (a[i] != b[i]) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+
+// TODO: export method size to math
+// math.size = size;
 
 /**
  * Function documentation