2020-10-19 21:08:55

docs/da/047.md

@@ -4,7 +4,7 @@
 
 In [1]:
 
-```
+```py
 import numpy as np
 
 ```
@@ -15,14 +15,14 @@ import numpy as np
 
 In [2]:
 
-```
+```py
 %%writefile myfile.txt
 2.1 2.3 3.2 1.3 3.1
 6.1 3.1 4.2 2.3 1.8
 
 ```
 
-```
+```py
 Writing myfile.txt
 
 ```
@@ -31,7 +31,7 @@ Writing myfile.txt
 
 In [3]:
 
-```
+```py
 data = []
 
 with open('myfile.txt') as f:
@@ -47,14 +47,14 @@ data = np.array(data)
 
 In [4]:
 
-```
+```py
 data
 
 ```
 
 Out[4]:
 
-```
+```py
 array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
        [ 6.1,  3.1,  4.2,  2.3,  1.8]])
 ```
@@ -63,7 +63,7 @@ array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
 
 In [5]:
 
-```
+```py
 data = np.loadtxt('myfile.txt')
 data
 
@@ -71,7 +71,7 @@ data
 
 Out[5]:
 
-```
+```py
 array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
        [ 6.1,  3.1,  4.2,  2.3,  1.8]])
 ```
@@ -80,14 +80,14 @@ array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
 
 In [6]:
 
-```
+```py
 %%writefile myfile.txt
 2.1, 2.3, 3.2, 1.3, 3.1
 6.1, 3.1, 4.2, 2.3, 1.8
 
 ```
 
-```
+```py
 Overwriting myfile.txt
 
 ```
@@ -98,7 +98,7 @@ Overwriting myfile.txt
 
 In [7]:
 
-```
+```py
 data = np.loadtxt('myfile.txt', delimiter=',')
 data
 
@@ -106,14 +106,14 @@ data
 
 Out[7]:
 
-```
+```py
 array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
        [ 6.1,  3.1,  4.2,  2.3,  1.8]])
 ```
 
 ### loadtxt 函数
 
-```
+```py
 loadtxt(fname, dtype=<type 'float'>, 
         comments='#', delimiter=None, 
         converters=None, skiprows=0, 
@@ -126,7 +126,7 @@ loadtxt(fname, dtype=<type 'float'>,
 
 In [8]:
 
-```
+```py
 %%writefile myfile.txt
 X Y Z MAG ANG
 2.1 2.3 3.2 1.3 3.1
@@ -134,28 +134,28 @@ X Y Z MAG ANG
 
 ```
 
-```
+```py
 Overwriting myfile.txt
 
 ```
 
 In [9]:
 
-```
+```py
 np.loadtxt('myfile.txt', skiprows=1)
 
 ```
 
 Out[9]:
 
-```
+```py
 array([[ 2.1,  2.3,  3.2,  1.3,  3.1],
        [ 6.1,  3.1,  4.2,  2.3,  1.8]])
 ```
 
 此外，有一个功能更为全面的 `genfromtxt` 函数，能处理更多的情况，但相应的速度和效率会慢一些。
 
-```
+```py
 genfromtxt(fname, dtype=<type 'float'>, comments='#', delimiter=None, 
            skiprows=0, skip_header=0, skip_footer=0, converters=None, 
            missing='', missing_values=None, filling_values=None, usecols=None, 
@@ -170,7 +170,7 @@ genfromtxt(fname, dtype=<type 'float'>, comments='#', delimiter=None,
 
 In [10]:
 
-```
+```py
 %%writefile myfile.txt
  -- BEGINNING OF THE FILE
 % Day, Month, Year, Skip, Power
@@ -180,14 +180,14 @@ In [10]:
 
 ```
 
-```
+```py
 Overwriting myfile.txt
 
 ```
 
 In [11]:
 
-```
+```py
 data = np.loadtxt('myfile.txt', 
                   skiprows=1,         #忽略第一行
                   dtype=np.int,      #数组类型
@@ -201,7 +201,7 @@ data
 
 Out[11]:
 
-```
+```py
 array([[   1,    1, 2000,   13],
        [   4,    1, 2000,   55]])
 ```
@@ -210,14 +210,14 @@ array([[   1,    1, 2000,   13],
 
 In [12]:
 
-```
+```py
 %%writefile myfile.txt
 2010-01-01 2.3 3.2
 2011-01-01 6.1 3.1
 
 ```
 
-```
+```py
 Overwriting myfile.txt
 
 ```
@@ -226,7 +226,7 @@ Overwriting myfile.txt
 
 In [13]:
 
-```
+```py
 import datetime
 
 def date_converter(s):
@@ -244,7 +244,7 @@ data
 
 Out[13]:
 
-```
+```py
 array([[datetime.datetime(2010, 1, 1, 0, 0), 2.3, 3.2],
        [datetime.datetime(2011, 1, 1, 0, 0), 6.1, 3.1]], dtype=object)
 ```
@@ -253,7 +253,7 @@ array([[datetime.datetime(2010, 1, 1, 0, 0), 2.3, 3.2],
 
 In [14]:
 
-```
+```py
 import os
 os.remove('myfile.txt')
 
@@ -285,7 +285,7 @@ os.remove('myfile.txt')
 
 In [15]:
 
-```
+```py
 data = np.array([[1,2], 
                  [3,4]])
 
@@ -295,14 +295,14 @@ np.savetxt('out.txt', data)
 
 In [16]:
 
-```
+```py
 with open('out.txt') as f:
     for line in f:
         print line,
 
 ```
 
-```
+```py
 1.000000000000000000e+00 2.000000000000000000e+00
 3.000000000000000000e+00 4.000000000000000000e+00
 
@@ -312,7 +312,7 @@ with open('out.txt') as f:
 
 In [17]:
 
-```
+```py
 data = np.array([[1,2], 
                  [3,4]])
 
@@ -322,14 +322,14 @@ np.savetxt('out.txt', data, fmt="%d") #保存为整数
 
 In [18]:
 
-```
+```py
 with open('out.txt') as f:
     for line in f:
         print line,
 
 ```
 
-```
+```py
 1 2
 3 4
 
@@ -339,7 +339,7 @@ with open('out.txt') as f:
 
 In [19]:
 
-```
+```py
 data = np.array([[1,2], 
                  [3,4]])
 
@@ -349,14 +349,14 @@ np.savetxt('out.txt', data, fmt="%.2f", delimiter=',') #保存为2位小数的
 
 In [20]:
 
-```
+```py
 with open('out.txt') as f:
     for line in f:
         print line,
 
 ```
 
-```
+```py
 1.00,2.00
 3.00,4.00
 
@@ -366,7 +366,7 @@ with open('out.txt') as f:
 
 In [21]:
 
-```
+```py
 data = np.array([[1+1j,2], 
                  [3,4]])
 
@@ -376,14 +376,14 @@ np.savetxt('out.txt', data, fmt="%.2f", delimiter=',') #保存为2位小数的
 
 In [22]:
 
-```
+```py
 with open('out.txt') as f:
     for line in f:
         print line,
 
 ```
 
-```
+```py
  (1.00+1.00j), (2.00+0.00j)
  (3.00+0.00j), (4.00+0.00j)
 
@@ -391,7 +391,7 @@ with open('out.txt') as f:
 
 更多参数：
 
-```
+```py
 savetxt(fname, 
         X, 
         fmt='%.18e', 
@@ -406,7 +406,7 @@ savetxt(fname,
 
 In [23]:
 
-```
+```py
 import os
 os.remove('out.txt')
 
@@ -432,7 +432,7 @@ os.remove('out.txt')
 
 In [24]:
 
-```
+```py
 a = np.array([[1.0,2.0], [3.0,4.0]])
 
 fname = 'afile.npy'
@@ -442,7 +442,7 @@ np.save(fname, a)
 
 In [25]:
 
-```
+```py
 aa = np.load(fname)
 aa
 
@@ -450,7 +450,7 @@ aa
 
 Out[25]:
 
-```
+```py
 array([[ 1.,  2.],
        [ 3.,  4.]])
 ```
@@ -459,7 +459,7 @@ array([[ 1.,  2.],
 
 In [26]:
 
-```
+```py
 import os
 os.remove('afile.npy')
 
@@ -469,7 +469,7 @@ os.remove('afile.npy')
 
 In [27]:
 
-```
+```py
 a = np.arange(10000.)
 
 ```
@@ -478,7 +478,7 @@ a = np.arange(10000.)
 
 In [28]:
 
-```
+```py
 np.savetxt('a.txt', a)
 
 ```
@@ -487,7 +487,7 @@ np.savetxt('a.txt', a)
 
 In [29]:
 
-```
+```py
 import os
 os.stat('a.txt').st_size
 
@@ -495,7 +495,7 @@ os.stat('a.txt').st_size
 
 Out[29]:
 
-```
+```py
 260000L
 ```
 
@@ -503,7 +503,7 @@ Out[29]:
 
 In [30]:
 
-```
+```py
 np.save('a.npy', a)
 
 ```
@@ -512,14 +512,14 @@ np.save('a.npy', a)
 
 In [31]:
 
-```
+```py
 os.stat('a.npy').st_size
 
 ```
 
 Out[31]:
 
-```
+```py
 80080L
 ```
 
@@ -527,7 +527,7 @@ Out[31]:
 
 In [32]:
 
-```
+```py
 os.remove('a.npy')
 os.remove('a.txt')
 
@@ -539,7 +539,7 @@ os.remove('a.txt')
 
 In [33]:
 
-```
+```py
 a = np.array([[1.0,2.0], 
               [3.0,4.0]])
 b = np.arange(1000)
@@ -550,7 +550,7 @@ b = np.arange(1000)
 
 In [34]:
 
-```
+```py
 np.savez('data.npz', a=a, b=b)
 
 ```
@@ -559,12 +559,12 @@ np.savez('data.npz', a=a, b=b)
 
 In [35]:
 
-```
+```py
 !unzip -l data.npz
 
 ```
 
-```
+```py
 Archive:  data.npz
   Length      Date    Time    Name
 ---------  ---------- -----   ----
@@ -579,7 +579,7 @@ Archive:  data.npz
 
 In [36]:
 
-```
+```py
 data = np.load('data.npz')
 
 ```
@@ -588,41 +588,41 @@ data = np.load('data.npz')
 
 In [37]:
 
-```
+```py
 data.keys()
 
 ```
 
 Out[37]:
 
-```
+```py
 ['a', 'b']
 ```
 
 In [38]:
 
-```
+```py
 data['a']
 
 ```
 
 Out[38]:
 
-```
+```py
 array([[ 1.,  2.],
        [ 3.,  4.]])
 ```
 
 In [39]:
 
-```
+```py
 data['b'].shape
 
 ```
 
 Out[39]:
 
-```
+```py
 (1000L,)
 ```
 
@@ -630,7 +630,7 @@ Out[39]:
 
 In [40]:
 
-```
+```py
 # 要先删除 data，否则删除时会报错
 del data
 
@@ -644,7 +644,7 @@ os.remove('data.npz')
 
 In [41]:
 
-```
+```py
 a = np.arange(20000.)
 
 ```
@@ -653,7 +653,7 @@ a = np.arange(20000.)
 
 In [42]:
 
-```
+```py
 np.savez('a.npz', a=a)
 os.stat('a.npz').st_size
 
@@ -661,7 +661,7 @@ os.stat('a.npz').st_size
 
 Out[42]:
 
-```
+```py
 160188L
 ```
 
@@ -669,7 +669,7 @@ Out[42]:
 
 In [43]:
 
-```
+```py
 np.savez_compressed('a2.npz', a=a)
 os.stat('a2.npz').st_size
 
@@ -677,7 +677,7 @@ os.stat('a2.npz').st_size
 
 Out[43]:
 
-```
+```py
 26885L
 ```
 
@@ -687,7 +687,7 @@ Out[43]:
 
 In [44]:
 
-```
+```py
 a = np.random.rand(20000.)
 
 ```
@@ -696,7 +696,7 @@ a = np.random.rand(20000.)
 
 In [45]:
 
-```
+```py
 np.savez('a.npz', a=a)
 os.stat('a.npz').st_size
 
@@ -704,7 +704,7 @@ os.stat('a.npz').st_size
 
 Out[45]:
 
-```
+```py
 160188L
 ```
 
@@ -712,7 +712,7 @@ Out[45]:
 
 In [46]:
 
-```
+```py
 np.savez_compressed('a2.npz', a=a)
 os.stat('a2.npz').st_size
 
@@ -720,7 +720,7 @@ os.stat('a2.npz').st_size
 
 Out[46]:
 
-```
+```py
 151105L
 ```
 
@@ -728,7 +728,7 @@ Out[46]:
 
 In [47]:
 
-```
+```py
 os.remove('a.npz')
 os.remove('a2.npz')