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Mnist数字识别卷积实现

作者:互联网

文章目录

设计流程:

1、准备数据

2、卷积、激活、池化(两层)

3、全连接层

4、计算准确率

代码实现:

# @XST1520203418
# 要天天开心呀
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data

from tensorflow.contrib.slim.python.slim.nets.inception_v3 import inception_v3_base


FLAGS = tf.app.flags.FLAGS

tf.app.flags.DEFINE_integer("is_train", 1, "指定程序是预测还是训练")


def full_connected():

    # 获取真实的数据
    mnist = input_data.read_data_sets("D:/ProgramData/机器学习/数据/MNIST/", one_hot=True)

    # 1、建立数据的占位符 x [None, 784]    y_true [None, 10]
    with tf.variable_scope("data"):
        x = tf.placeholder(tf.float32, [None, 784])

        y_true = tf.placeholder(tf.int32, [None, 10])

    # 2、建立一个全连接层的神经网络 w [784, 10]   b [10]
    with tf.variable_scope("fc_model"):
        # 随机初始化权重和偏置
        weight = tf.Variable(tf.random_normal([784, 10], mean=0.0, stddev=1.0), name="w")

        bias = tf.Variable(tf.constant(0.0, shape=[10]))

        # 预测None个样本的输出结果matrix [None, 784]* [784, 10] + [10] = [None, 10]
        y_predict = tf.matmul(x, weight) + bias

    # 3、求出所有样本的损失,然后求平均值
    with tf.variable_scope("soft_cross"):

        # 求平均交叉熵损失
        loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y_true, logits=y_predict))

    # 4、梯度下降求出损失
    with tf.variable_scope("optimizer"):

        train_op = tf.train.GradientDescentOptimizer(0.1).minimize(loss)

    # 5、计算准确率
    with tf.variable_scope("acc"):

        equal_list = tf.equal(tf.argmax(y_true, 1), tf.argmax(y_predict, 1))

        # equal_list  None个样本   [1, 0, 1, 0, 1, 1,..........]
        accuracy = tf.reduce_mean(tf.cast(equal_list, tf.float32))

    # 收集变量 单个数字值收集
    tf.summary.scalar("losses", loss)
    tf.summary.scalar("acc", accuracy)

    # 高纬度变量收集
    tf.summary.histogram("weightes", weight)
    tf.summary.histogram("biases", bias)

    # 定义一个初始化变量的op
    init_op = tf.global_variables_initializer()

    # 定义一个合并变量de op
    merged = tf.summary.merge_all()

    # 创建一个saver
    saver = tf.train.Saver()

    # 开启会话去训练
    with tf.Session() as sess:
        # 初始化变量
        sess.run(init_op)

        # 建立events文件,然后写入
        filewriter = tf.summary.FileWriter("./summary/test01/", graph=sess.graph)

        if FLAGS.is_train == 1:

            # 迭代步数去训练,更新参数预测
            for i in range(2000):

                # 取出真实存在的特征值和目标值
                mnist_x, mnist_y = mnist.train.next_batch(50)

                # 运行train_op训练
                sess.run(train_op, feed_dict={x: mnist_x, y_true: mnist_y})

                # 写入每步训练的值
                summary = sess.run(merged, feed_dict={x: mnist_x, y_true: mnist_y})

                filewriter.add_summary(summary, i)

                print("训练第%d步,准确率为:%f" % (i, sess.run(accuracy, feed_dict={x: mnist_x, y_true: mnist_y})))

            # 保存模型
            saver.save(sess, "./tmp/ckpt/fc_model")
        else:
            # 加载模型
            saver.restore(sess, "./tmp/ckpt/fc_model")

            # 如果是0,做出预测
            for i in range(100):

                # 每次测试一张图片 [0,0,0,0,0,1,0,0,0,0]
                x_test, y_test = mnist.test.next_batch(1)

                print("第%d张图片,手写数字图片目标是:%d, 预测结果是:%d" % (
                    i,
                    tf.argmax(y_test, 1).eval(),
                    tf.argmax(sess.run(y_predict, feed_dict={x: x_test, y_true: y_test}), 1).eval()
                ))
    return None

if __name__ == "__main__":
    full_connected()

在这里插入图片描述在这里插入图片描述

自定义卷积模型实现:

# @XST1520203418
# 要天天开心呀
import tensorflow as tf
from tensorflow.examples.tutorials.mnist import input_data
from tensorflow.contrib.slim.python.slim.nets.inception_v3 import inception_v3_base
FLAGS = tf.app.flags.FLAGS

tf.app.flags.DEFINE_integer("is_train", 1, "指定程序是预测还是训练")
# 定义一个初始化权重的函数
def weight_variables(shape):
    w = tf.Variable(tf.random_normal(shape=shape, mean=0.0, stddev=1.0))
    return w

# 定义一个初始化偏置的函数
def bias_variables(shape):
    b = tf.Variable(tf.constant(0.0, shape=shape))
    return b


def model():
    """
    自定义的卷积模型
    :return:
    """
    # 1、准备数据的占位符 x [None, 784]  y_true [None, 10]
    with tf.variable_scope("data"):
        x = tf.placeholder(tf.float32, [None, 784])

        y_true = tf.placeholder(tf.int32, [None, 10])

    # 2、一卷积层 卷积: 5*5*1,32个,strides=1 激活: tf.nn.relu 池化
    with tf.variable_scope("conv1"):
        # 随机初始化权重, 偏置[32]
        w_conv1 = weight_variables([5, 5, 1, 32])

        b_conv1 = bias_variables([32])

        # 对x进行形状的改变[None, 784]  [None, 28, 28, 1]
        x_reshape = tf.reshape(x, [-1, 28, 28, 1])

        # [None, 28, 28, 1]-----> [None, 28, 28, 32]
        x_relu1 = tf.nn.relu(tf.nn.conv2d(x_reshape, w_conv1, strides=[1, 1, 1, 1], padding="SAME") + b_conv1)

        # 池化 2*2 ,strides2 [None, 28, 28, 32]---->[None, 14, 14, 32]
        x_pool1 = tf.nn.max_pool(x_relu1, ksize=[1, 2, 2, 1], strides=[1, 2, 2, 1], padding="SAME")

    # 3、二卷积层卷积: 5*5*32,64个filter,strides=1 激活: tf.nn.relu 池化:
    with tf.variable_scope("conv2"):
        # 随机初始化权重,  权重:[5, 5, 32, 64]  偏置[64]
        w_conv2 = weight_variables([5, 5, 32, 64])

        b_conv2 = bias_variables([64])

        # 卷积,激活,池化计算
        # [None, 14, 14, 32]-----> [None, 14, 14, 64]
        x_relu2 = tf.nn.relu(tf.nn.conv2d(x_pool1, w_conv2, strides=[1, 1, 1, 1], padding="SAME") + b_conv2)

        # 池化 2*2, strides 2, [None, 14, 14, 64]---->[None, 7, 7, 64]
        x_pool2 = tf.nn.max_pool(x_relu2, ksize=[1, 2, 2, 1], strides=[1, 2, 2, 1], padding="SAME")

    # 4、全连接层 [None, 7, 7, 64]--->[None, 7*7*64]*[7*7*64, 10]+ [10] =[None, 10]
    with tf.variable_scope("conv2"):

        # 随机初始化权重和偏置
        w_fc = weight_variables([7 * 7 * 64, 10])

        b_fc = bias_variables([10])

        # 修改形状 [None, 7, 7, 64] --->None, 7*7*64]
        x_fc_reshape = tf.reshape(x_pool2, [-1, 7 * 7 * 64])

        # 进行矩阵运算得出每个样本的10个结果
        y_predict = tf.matmul(x_fc_reshape, w_fc) + b_fc

    return x, y_true, y_predict


def conv_fc():
    # 获取真实的数据
    mnist = input_data.read_data_sets("./data/mnist/input_data/", one_hot=True)

    # 定义模型,得出输出
    x, y_true, y_predict = model()

    # 进行交叉熵损失计算
    # 3、求出所有样本的损失,然后求平均值
    with tf.variable_scope("soft_cross"):
        # 求平均交叉熵损失# 求平均交叉熵损失
        loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y_true, logits=y_predict))

    # 4、梯度下降求出损失
    with tf.variable_scope("optimizer"):
        train_op = tf.train.GradientDescentOptimizer(0.0001).minimize(loss)

    # 5、计算准确率
    with tf.variable_scope("acc"):
        equal_list = tf.equal(tf.argmax(y_true, 1), tf.argmax(y_predict, 1))

        # equal_list  None个样本   [1, 0, 1, 0, 1, 1,..........]
        accuracy = tf.reduce_mean(tf.cast(equal_list, tf.float32))

    # 定义一个初始化变量的op
    init_op = tf.global_variables_initializer()

    # 开启回话运行
    with tf.Session() as sess:
        sess.run(init_op)

        # 循环去训练
        for i in range(1000):

            # 取出真实存在的特征值和目标值
            mnist_x, mnist_y = mnist.train.next_batch(50)

            # 运行train_op训练
            sess.run(train_op, feed_dict={x: mnist_x, y_true: mnist_y})

            print("训练第%d步,准确率为:%f" % (i, sess.run(accuracy, feed_dict={x: mnist_x, y_true: mnist_y})))


    return None


if __name__ == "__main__":
    conv_fc()

在这里插入图片描述

标签:10,None,卷积,64,Mnist,tf,识别,true,mnist
来源: https://blog.csdn.net/XST1520203418/article/details/122025891