importpandasaspddf=pd.read_json('/Users/chenyi/Documents/News_Category_Dataset.json',lines=True)df.head()categories=df.groupby('category')print("totalcategories...

fromkeras.datasetsimportimdb#num_words表示加载影评时，确保影评里面的单词使用频率保持在前1万位，于是有些很少见的生僻词在数据加载时会舍弃掉(train_data,train_labels),(test_data,test_labels)=imdb.load_data(num_wor...

importtensorflowastffromtensorflowimportkerasfromkerasimportSequential,datasets,layers,optimizers,metricsdefpreprocess(x,y):"""数据处理函数"""x=tf.cast(x,dtype=tf.flo...

importnumpyasnpimportmatplotlib.pyplotaspltfrommpl_toolkits.mplot3dimportAxes3Ddefhimmeblau(x):return(x[0]**2+x[1]-11)**2+(x[0]+x[1]**2-7)**2x=np.arange(-6,6,0....

      ...

importtensorflowastfx=tf.constant(1.)w1=tf.constant(2.)b1=tf.constant(1.)w2=tf.constant(2.)b2=tf.constant(1.)withtf.GradientTape(persistent=True)astape:tape.wat...

importtensorflowastfx=tf.random.normal([2,4])w=tf.random.normal([4,3])b=tf.zeros([3])y=tf.constant([2,0])withtf.GradientTape()astape:tape.watch([w,b])#axis=1，表示...

    importtensorflowastfx=tf.random.normal([1,3])w=tf.ones([3,1])b=tf.ones([1])y=tf.constant([1])withtf.GradientTape()astape:tape.watch([w,b...

importtensorflowastfx=tf.random.normal([2,4])w=tf.random.normal([4,3])b=tf.zeros([3])y=tf.constant([2,0])withtf.GradientTape()astape:tape.watch([w,b])prob=tf.nn...

        importtensorflowastfa=tf.linspace(-10.,10.,10)awithtf.GradientTape()astape:tape.watch(a)y=tf.sigmoid(a)grads=tap...

  importtensorflowastfw=tf.constant(1.)x=tf.constant(2.)y=x*wwithtf.GradientTape()astape:tape.watch([w])y2=x*wgrad1=tape.gradient(y,[w])grad1withtf.Gr...

importtensorflowastfy=tf.constant([1,2,3,0,2])y=tf.one_hot(y,depth=4)#max_label=3种y=tf.cast(y,dtype=tf.float32)out=tf.random.normal([5,4])outloss1=tf.reduce_mea...

sigmoid  out'=sigmoid(out)#把输出值压缩在0-1importtensorflowastfa=tf.linspace(-6.,6,10)atf.sigmoid(a)x=tf.random.normal([1,28,28])*5tf.reduce_min(x),tf.reduc...

out=f(X@W+b)out=relut(X@W+b)    importtensorflowastfx=tf.random.normal([4,784])net=tf.keras.layers.Dense(512)out=net(x)out.shapenet.kernel.s...

classNeuralNetWork:def__init__(self):'''初始化网络，设置输入层，中间层，输出层的节点数'''passdeffit(self):'''根据训练数据，不断更新神经网络层之间的链路权重'''passdefevaluate(self):'''输入新数据，网络给出对新数据的判断结果'''p...