TensorFlow > sine curveの学習 > v0.6 > placeholderを使った結果が使わない結果と同じになった

```txt:動作環境
GeForce GTX 1070 (8GB)
ASRock Z170M Pro4S [Intel Z170chipset]
Ubuntu 14.04 LTS desktop amd64
TensorFlow v0.11
cuDNN v5.1 for Linux
CUDA v8.0
Python 2.7.6
IPython 5.1.0 -- An enhanced Interactive Python.
```

v0.1 http://qiita.com/7of9/items/b364d897b95476a30754

sine curveを学習するコードをplaceholder使用に変更している。

### input.csv生成

http://qiita.com/7of9/items/b364d897b95476a30754#データ生成部

### original (placeholder不使用)

```linreg2.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
import tensorflow as tf
import tensorflow.contrib.slim as slim

# ファイル名の Queue を作成
filename_queue = tf.train.string_input_producer(["input.csv"])

# CSV を parse
reader = tf.TextLineReader()
key, value = reader.read(filename_queue)
input1, output = tf.decode_csv(value, record_defaults=[[0.], [0.]])
inputs = tf.pack([input1])
output = tf.pack([output])

batch_size=4 # [4]
inputs_batch, output_batch = tf.train.shuffle_batch([inputs, output], batch_size, capacity=40, min_after_dequeue=batch_size)

## NN のグラフ生成
hiddens = slim.stack(inputs_batch, slim.fully_connected, [1,7,7,7], 
  activation_fn=tf.nn.sigmoid, scope="hidden")
prediction = slim.fully_connected(hiddens, 1, activation_fn=tf.nn.sigmoid, scope="output")

loss = tf.contrib.losses.mean_squared_error(prediction, output_batch)
#train_op = slim.learning.create_train_op(loss, tf.train.AdamOptimizer(0.01))
train_op = slim.learning.create_train_op(loss, tf.train.AdamOptimizer(0.001))

init_op = tf.initialize_all_variables()

with tf.Session() as sess:
  coord = tf.train.Coordinator()
  threads = tf.train.start_queue_runners(sess=sess, coord=coord)

  try:
    sess.run(init_op)
    for i in range(30000): #[10000]
      _, t_loss = sess.run([train_op, loss])
      if (i+1) % 100 == 0:
        print("%d,%f" % (i+1, t_loss))
#        print("%d,%f,#step, loss" % (i+1, t_loss))
  finally:
    coord.request_stop()

  coord.join(threads)
```


### v0.6 (placeholder使用)

.eval()を使わない方針とした。
http://qiita.com/7of9/items/40a7cfc741f4b11f50d2


```linreg2_noEval.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
import tensorflow as tf
import tensorflow.contrib.slim as slim

# ファイル名の Queue を作成
filename_queue = tf.train.string_input_producer(["input.csv"])

# CSV を parse
reader = tf.TextLineReader()
key, value = reader.read(filename_queue)
input1, output = tf.decode_csv(value, record_defaults=[[0.], [0.]])
inputs = tf.pack([input1])
output = tf.pack([output])

batch_size=4 # [4]
inputs_batch, output_batch = tf.train.shuffle_batch([inputs, output], batch_size, capacity=40, min_after_dequeue=batch_size)

input_ph = tf.placeholder("float", [None,1])
output_ph = tf.placeholder("float",[None,1])

## NN のグラフ生成
hiddens = slim.stack(input_ph, slim.fully_connected, [1,7,7,7], 
  activation_fn=tf.nn.sigmoid, scope="hidden")
prediction = slim.fully_connected(hiddens, 1, activation_fn=tf.nn.sigmoid, scope="output")
loss = tf.contrib.losses.mean_squared_error(prediction, output_ph)

#train_op = slim.learning.create_train_op(loss, tf.train.AdamOptimizer(0.01))
train_op = slim.learning.create_train_op(loss, tf.train.AdamOptimizer(0.001))

#def feed_dict(inputs, output):
#    return {input_ph: inputs.eval(), output_ph: output.eval()}

init_op = tf.initialize_all_variables()

with tf.Session() as sess:
  coord = tf.train.Coordinator()
  threads = tf.train.start_queue_runners(sess=sess, coord=coord)

  try:
    sess.run(init_op)
    for i in range(30000): #[10000]
#if 1 // no eval()
      inpbt, outbt = sess.run([inputs_batch, output_batch])
      _, t_loss = sess.run([train_op, loss], feed_dict={input_ph:inpbt, output_ph: outbt})
#else
#      _, t_loss = sess.run([train_op, loss], feed_dict=feed_dict(inputs_batch, output_batch))
#endif      
      if (i+1) % 100 == 0:
        print("%d,%f" % (i+1, t_loss))
#        print("%d,%f,#step, loss" % (i+1, t_loss))
  finally:
    coord.request_stop()

  coord.join(threads)
```

## 結果

python linreg2.py > log.learn_original
python linreg2_noEval.py > log.learn_noEval

matplotlibコード on Jupyter

```py
%matplotlib inline

import numpy as np
import matplotlib.pyplot as plt

data1 = np.loadtxt('log.learn_original', delimiter=',')
data2 = np.loadtxt('log.learn_noEval', delimiter=',')

input1 = data1[:,0]
output1 = data1[:,1]
input2 = data2[:,0]
output2 = data2[:,1]

fig = plt.figure()
ax1 = fig.add_subplot(2,1,1)
ax2 = fig.add_subplot(2,1,2)

#ax.plot(input1, output1, color='black', linestyle='dotted', label='rate=0.001')
ax1.plot(input1, output1, color='black', linestyle='solid', label='original')
ax2.plot(input2, output2, color='red', linestyle='solid', label='placeholder')
#ax.scatter(input1, output1)

ax1.set_title('loss')
ax1.set_xlabel('step')
ax1.set_ylabel('loss')
ax1.grid(True)
ax1.legend()

#ax2.set_title('loss')
ax2.set_xlabel('step')
ax2.set_ylabel('loss')
ax2.grid(True)
ax2.legend()

fig.show()
```

![qiita.png](https://qiita-image-store.s3.amazonaws.com/0/32870/059d5407-2594-c40e-a5a6-21423bc06532.png)


同じような結果がようやく得られた。

11/14から今日(11/20)まではまっていたので、結構苦労した。