feat(*): add error hadling in defineConfig() api

src/wink-perceptron.js

@@ -183,10 +183,10 @@ var perceptron = function () {
 
       v = features[ f ];
       adjustWt( f, v, truth );
-      if ( guess ) adjustWt( f, -v, guess );
+      if ( guess !== 'unknown' ) adjustWt( f, -v, guess );
     }
     adjustBs( +1, truth );
-    if ( guess ) adjustBs( -1, guess );
+    if ( guess !== 'unknown' ) adjustBs( -1, guess );
   }; // adjustWeights()
 
   var learnFromData = function ( data ) {
@@ -196,7 +196,7 @@ var perceptron = function () {
     var j, k;
 
     // Starting from **1** ensures that we iterate **maxIterations** times.
-    for ( j = 1; j < maxIterations; j += 1 ) {
+    for ( j = 0; j < maxIterations; j += 1 ) {
       for ( k = 0; k < data.length; k += 1 ) {
         guess = predict( data[ k ][ 0 ] );
         if ( guess !== data[ k ][ 1 ].label ) adjustWeights( data[ k ], guess );
@@ -216,7 +216,7 @@ var perceptron = function () {
     var j, k, l;
 
     // Starting from **1** ensures that we iterate **maxIterations** times.
-    for ( j = 1; j < maxIterations; j += 1 ) {
+    for ( j = 0; j < maxIterations; j += 1 ) {
       for ( k = 0; k < data.length; k += 1 ) {
         features = featureExtractor( data[ k ] );
         for ( l = 0; l < features.length; l += 1 ) {
@@ -282,13 +282,22 @@ var perceptron = function () {
    * // -> { shuffleData: true, maxIterations: 9, featureExtractor: null }
   */
   var defineConfig = function ( config ) {
+    if ( !helpers.object.isObject( config ) ) {
+      throw Error( 'wink-perceptron: config must be an object, instead found: ' + ( typeof config ) );
+    }
     // Convert 'truthy -> true' or `falsy -> false`. This also implies that
     // default is **`false`**.
     shuffleData = !!config.shuffleData;
     // Default # of maximum iteration is **6**.
     maxIterations = config.maxIterations || maxIterations;
+    if ( maxIterations < 1 ) {
+      throw Error( 'wink-perceptron: maxIterations should be >1' );
+    }
     // Ordered Set Of Features Extractor function; default is none!
     featureExtractor = config.featureExtractor || featureExtractor;
+    if ( ( featureExtractor !== null ) && ( typeof featureExtractor !== 'function' )  ) {
+      throw Error( 'wink-perceptron: featureExtractor must be a function, instead found: ' + ( typeof featureExtractor ) );
+    }
 
     return ( { shuffleData: shuffleData, maxIterations: maxIterations, featureExtractor: featureExtractor } );
   }; // defineConfig()

test/wink-perceptron-specs.js

@@ -47,18 +47,20 @@ var extractFeatures = function ( e ) {
 // IRIS Data is sourced from UC Irvine Machine Learning Repository;
 // source: https://archive.ics.uci.edu/ml/datasets/iris
 // Prepare data:
+// Training data preparation.
 lines = fs.readFileSync( './test/data/iris-data-train.csv', 'utf8' ).split( '\n' );
 lines.pop();
 td = [];
 lines.forEach( function ( e ) {
   td.push( e.split( ',' ) );
 } );
-
+// The `rawTrainingData` will now be a copy of `td` array.
 rawTrainingData = td.slice( 0 );
 td.forEach( function ( e ) {
   trainingData.push( extractFeatures( e )[ 0 ] );
 } );
 
+// Test data preparation.
 lines = fs.readFileSync( './test/data/iris-data-test.csv', 'utf8' ).split( '\n' );
 lines.pop();
 td = [];
@@ -70,12 +72,31 @@ td.forEach( function ( e ) {
 } );
 
 // Tests
-describe( 'instantiate perceptron ', function () {
+describe( 'instantiate perceptron', function () {
   it( 'must return 3 methods', function () {
     expect( Object.keys( perceptron() ).length ).to.equal( 3 );
   } );
 } );
 
+describe( 'defineConfig', function () {
+  it( 'should throw error if config is not passed', function () {
+      expect( perceptron().defineConfig.bind( undefined, undefined ) ).to.throw( 'wink-perceptron: config must be an object, instead found:' );
+  } );
+
+  it( 'should throw error maxIterations <1', function () {
+      expect( perceptron().defineConfig.bind( undefined, { maxIterations: -1 } ) ).to.throw( 'wink-perceptron: maxIterations should be >1' );
+  } );
+
+  it( 'should throw error featureExtractor must be a function', function () {
+      expect( perceptron().defineConfig.bind( undefined, { featureExtractor: 1 } ) ).to.throw( 'wink-perceptron: featureExtractor must be a function, instead found:' );
+  } );
+
+  it( 'should default configuration with empty config input', function () {
+      expect( perceptron().defineConfig( {} ) )
+      .to.deep.equal( { shuffleData: false, maxIterations: 9, featureExtractor: null } );
+  } );
+} );
+
 describe( 'train & predict using extracted features from iris data', function () {
   var p = perceptron();