backpropagation
==============================

.. js:function:: ConvolutionalLayer.backpropagation() 

    誤差逆伝播

ソース
^^^^^^

.. code-block:: js

            backpropagation() {
                var lap = new Lap(this.backwardTime);
    
                if (this.nextLayer) {
                    // 最後のレイヤーでない場合
    
                    this.deltaY = this.nextLayer.deltaX;
                }
    
                this.cpuDeltaZ();
                lap.Time();
    
                this.cpuDeltaBias();
                lap.Time();
    
                this.gpuDeltaWeight();
    
                if(miniBatchIdx == 0 || Math_random() < 0.01){
    
                    var delta_w = new Float32Array(this.deltaWeight.dt);
                    this.cpuDeltaWeight();
    
                    var diff = this.deltaWeight.diff(delta_w);
                    if(0.00001 < diff){
                        console.log("CNN delta-W diff:%f", diff);
                    }
                }
    
                lap.Time();
    
                if(! (this.prevLayer instanceof InputLayer)){
                    // 直前が入力層でない場合
    
                    this.gpuDeltaX();
    
                    if(miniBatchIdx == 0 || Math_random() < 0.01){
    
                        var delta_x1 = new Float32Array(this.deltaX.dt);
    
                        this.cpuDeltaX();
    
                        var delta_x2 = this.cpuDeltaX2();
                        var diff1 = this.deltaX.diff(delta_x1);
                        var diff2 = this.deltaX.diff(delta_x2);
                        if(0.00001 < diff1 || 0.00001 < diff2){
                            console.log("CNN delta-X diff:%f %f", diff1, diff2);
                        }
                    }
                }
                lap.Time();
            }