提问者:小点点

TensorFlow:使用CSV数据的简单线性回归


我是TensorFlow的极端初学者,我的任务是使用我的csv数据进行简单的线性回归,其中包含2列,高度

使用高度我应该预测SoC

我完全不知道我必须在代码的“拟合所有训练数据”部分添加什么。我看过其他线性回归模型,它们的代码令人难以置信,比如这个:

with tf.Session() as sess:
sess.run(init)
for epoch in range(training_epochs):
    sess.run(training_step,feed_dict={X:train_x,Y:train_y})
    cost_history = np.append(cost_history,sess.run(cost,feed_dict={X: train_x,Y: train_y}))

#calculate mean square error 
pred_y = sess.run(y_, feed_dict={X: test_x})
mse = tf.reduce_mean(tf.square(pred_y - test_y))
print("MSE: %.4f" % sess.run(mse)) 

#plot cost
plt.plot(range(len(cost_history)),cost_history)
plt.axis([0,training_epochs,0,np.max(cost_history)])
plt.show()

fig, ax = plt.subplots()
ax.scatter(test_y, pred_y)
ax.plot([test_y.min(), test_y.max()], [test_y.min(), test_y.max()], 'k--', lw=3)
ax.set_xlabel('Measured')
ax.set_ylabel('Predicted')
plt.show()

我刚刚能够使用本指南从我的CSV文件中获取数据而不会出错:

TensorFlow:从CSV文件中读取和使用数据

完整代码:

import tensorflow as tf
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
%matplotlib inline
rng = np.random

from numpy import genfromtxt
from sklearn.datasets import load_boston

# Parameters
learning_rate = 0.01
training_epochs = 1000
display_step = 50
n_samples = 221

X = tf.placeholder("float") # create symbolic variables
Y = tf.placeholder("float")

filename_queue = tf.train.string_input_producer(["battdata.csv"],shuffle=False)

reader = tf.TextLineReader(skip_header_lines=1)
key, value = reader.read(filename_queue)

# Default values, in case of empty columns. Also specifies the type of the
# decoded result.
record_defaults = [[1.], [1.]]
col1, col2= tf.decode_csv(
    value, record_defaults=record_defaults)
features = tf.stack([col1])

# Set model weights
W = tf.Variable(rng.randn(), name="weight")
b = tf.Variable(rng.randn(), name="bias")

# Construct a linear model
pred = tf.add(tf.multiply(col1, W), b) # XW + b <- y = mx + b  where W is gradient, b is intercept

# Mean squared error
cost = tf.reduce_sum(tf.pow(pred-col2, 2))/(2*n_samples)

# Gradient descent
optimizer = tf.train.GradientDescentOptimizer(learning_rate).minimize(cost)

# Initializing the variables
init = tf.global_variables_initializer()

with tf.Session() as sess:
    # Start populating the filename queue.
    coord = tf.train.Coordinator()
    threads = tf.train.start_queue_runners(coord=coord)
    sess.run(init)

    # Fit all training data
    for epoch in range(training_epochs):
        _, cost_value = sess.run([optimizer,cost])
        for (x, y) in zip(col2, col1):
                sess.run(optimizer, feed_dict={X: x, Y: y})

            #Display logs per epoch step
        if (epoch+1) % display_step == 0:
            c = sess.run(cost, feed_dict={X: col2, Y:col1})
            print( "Epoch:", '%04d' % (epoch+1), "cost=", "{:.9f}".format(c), \
                "W=", sess.run(W), "b=", sess.run(b))

        print("Optimization Finished!")
        training_cost = sess.run(cost, feed_dict={X: col2, Y: col1})
        print ("Training cost=", training_cost, "W=", sess.run(W), "b=", sess.run(b), '\n')

        #Graphic display
        plt.plot(train_X, train_Y, 'ro', label='Original data')
        plt.plot(train_X, sess.run(W) * col2 + sess.run(b), label='Fitted line')
        plt.legend()
        plt.show()

    coord.request_stop()
    coord.join(threads)

错误:

INFO:tensorflow:Error reported to Coordinator: , Attempted to use a closed Session. --------------------------------------------------------------------------- TypeError Traceback (most recent call last) in () 8 for epoch in range(training_epochs): 9 _, cost_value = sess.run([optimizer,cost]) ---

C:\用户\Shiina\Anaconda3\envs\Tensorflow\lib\site-包\Tensorflow\python\框架\ops.py在iter(self)514 TypeError:当调用.515 """ --

TypeError:“张量”对象不可迭代。


共1个答案

匿名用户

错误是因为您试图在中迭代zip(col2, col1)中的(x,y)张量,这是不允许的。代码的其他问题是您设置了输入管道队列,然后您还试图通过feed_dict{}输入,这是错误的。您的训练部分应该如下所示:

with tf.Session() as sess:
# Start populating the filename queue.
coord = tf.train.Coordinator()
threads = tf.train.start_queue_runners(coord=coord)
sess.run(init)

# Fit all training data
for epoch in range(training_epochs):
    _, cost_value = sess.run([optimizer,cost])

        #Display logs per epoch step
    if (epoch+1) % display_step == 0:
        c = sess.run(cost)
        print( "Epoch:", '%04d' % (epoch+1), "cost=", "{:.9f}".format(c), \
            "W=", sess.run(W), "b=", sess.run(b))

    print("Optimization Finished!")
    training_cost = sess.run(cost)
    print ("Training cost=", training_cost, "W=", sess.run(W), "b=", sess.run(b), '\n')

#Plot data after completing training
train_X = []
train_Y = []
for i in range(input_size): #Your input data size to loop through once
    X, Y = sess.run([col1, pred]) # Call pred, to get the prediction with the updated weights
    train_X.append(X)
    train_Y.append(y)
    #Graphic display
plt.plot(train_X, train_Y, 'ro', label='Original data')
plt.legend()
plt.show()

coord.request_stop()
coord.join(threads)