1.在搭建网络开始时,会调用到 keras.models的Sequential()方法,返回一个model参数表示模型
2.model参数里面有个fit()方法,用于把训练集传进网络。fit()返回一个参数,该参数包含训练集和验证集的准确性acc和错误值loss,用这些数据画成图表即可。
如:
history=model.fit(x_train, y_train, batch_size=32, epochs=5, validation_split=0.25) #获取数据 #########画图 acc = history.history['acc'] #获取训练集准确性数据 val_acc = history.history['val_acc'] #获取验证集准确性数据 loss = history.history['loss'] #获取训练集错误值数据 val_loss = history.history['val_loss'] #获取验证集错误值数据 epochs = range(1,len(acc)+1) plt.plot(epochs,acc,'bo',label='Trainning acc') #以epochs为横坐标,以训练集准确性为纵坐标 plt.plot(epochs,val_acc,'b',label='Vaildation acc') #以epochs为横坐标,以验证集准确性为纵坐标 plt.legend() #绘制图例,即标明图中的线段代表何种含义 plt.figure() #创建一个新的图表 plt.plot(epochs,loss,'bo',label='Trainning loss') plt.plot(epochs,val_loss,'b',label='Vaildation loss') plt.legend() ##绘制图例,即标明图中的线段代表何种含义 plt.show() #显示所有图表
得到效果:
完整代码:
import keras from keras.datasets import mnist from keras.layers import Conv2D, MaxPool2D, Dense, Flatten,Dropout from keras.models import Sequential import matplotlib.pyplot as plt (x_train, y_train), (x_test, y_test) = mnist.load_data() x_train = x_train.reshape(-1, 28, 28, 1) x_test = x_test.reshape(-1, 28, 28, 1) x_train = x_train / 255. x_test = x_test / 255. y_train = keras.utils.to_categorical(y_train) y_test = keras.utils.to_categorical(y_test) model = Sequential() model.add(Conv2D(20,(5,5),strides=(1,1),input_shape=(28,28,1),padding='valid',activation='relu',kernel_initializer='uniform')) model.add(MaxPool2D(pool_size=(2,2),strides=(2,2))) model.add(Conv2D(64,(5,5),strides=(1,1),padding='valid',activation='relu',kernel_initializer='uniform')) model.add(MaxPool2D(pool_size=(2,2),strides=(2,2))) model.add(Flatten()) model.add(Dense(500,activation='relu')) model.add(Dropout(0.2)) model.add(Dense(10,activation='softmax')) model.compile('sgd', loss='categorical_crossentropy', metrics=['accuracy']) #随机梯度下降 history=model.fit(x_train, y_train, batch_size=32, epochs=5, validation_split=0.25) #获取数据 #########画图 acc = history.history['acc'] #获取训练集准确性数据 val_acc = history.history['val_acc'] #获取验证集准确性数据 loss = history.history['loss'] #获取训练集错误值数据 val_loss = history.history['val_loss'] #获取验证集错误值数据 epochs = range(1,len(acc)+1) plt.plot(epochs,acc,'bo',label='Trainning acc') #以epochs为横坐标,以训练集准确性为纵坐标 plt.plot(epochs,val_acc,'b',label='Vaildation acc') #以epochs为横坐标,以验证集准确性为纵坐标 plt.legend() #绘制图例,即标明图中的线段代表何种含义 plt.figure() #创建一个新的图表 plt.plot(epochs,loss,'bo',label='Trainning loss') plt.plot(epochs,val_loss,'b',label='Vaildation loss') plt.legend() ##绘制图例,即标明图中的线段代表何种含义
以上这篇使用Keras画神经网络准确性图教程就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。