Data Algorithm learn of Numpy


Author:チューガー
2018-11-28   19:11:09
IDE: Pycharm2018.03   Anaconda 3.5.1 Python 3.7   
KeyWord :  NumPy 
Explain:更新[Explain:こうしん]
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  1 # -*- coding: utf-8 -*-
  2 # ---------------------------------
  3 
  4 """
  5 # Author  : chu ge
  6 # Function: Numpy
  7 #
  8 """
  9 
 10 # ---------------------------------
 11 '''
 12 # --------------------------------
 13 #      
 14 # 1.   
 15 # 2.    
 16 # 3.     
 17 # --------------------------------
 18 '''
 19 # 1.   、
 20 import sys
 21 import os
 22 
 23 # 2.    
 24 import numpy as np
 25 from scipy import linalg
 26 import pandas as pd
 27 import matplotlib.pyplot as plt
 28 import seaborn as sns
 29 
 30 import timeit
 31 import numpy.random as np_random
 32 from numpy.linalg import inv, qr
 33 from random import normalvariate
 34 
 35 import pylab
 36 #
 37 '''
 38 ============================================================================
 39 #》》》》》》》》》》》》》》》》》》》》》》》》
 40 
 41 ----------------------------------------------
 42 Numpy
 43              、     ,         ,       Numpy   list   
 44     NumPy Python          。                ,                   。
 45     
 46                ndarray
 47  48  49         •       、     ,       
 50         •    C、C++、Fortran     Python   
 51         •    Python           ,NumPy            
 52              ,               。
 53 
 54 Scipy
 55          NumPy      、    、  、      
 56     
 57 Pandas
 58           Numpy            ,         。
 59     n                        。
 60     n          。
 61     n                      。
 62     n        (     )        。
 63     n         。
 64     n             (    SQL)           。
 65     o     :Series DataFrame
 66     
 67 matplotlib
 68     Python   
 69     
 70 nltk
 71              (Natural Language Toolkit)
 72     n   :pip install -U nltk
 73     n   :import nltk
 74     n      :nltk.download()
 75     n     
 76     n     
 77     n     
 78     n     
 79     n     
 80 
 81 igraph
 82               
 83     o   :
 84         n pip install -U python-igraph
 85         n conda install -c marufr python-igraph=0.7.1.post6
 86 Scikit-learn
 87     o Scikit-learn    Scipy            Python  。
 88         n   :pip install -U scikit-learn / conda install scikit-learn
 89 ----------------------------------------------
 90 
 91 Numpy
 92 ----------------------------------------------
 93         
 94 array                    (  、  、         )   ndarray。
 95                          dtype,      dtype。          。
 96 asarray                   darray,          ndarray      。
 97 arange                    range,     ndarray     。
 98 ones,ones_like             dtype     1  。ones_like         ,
 99                            dtype     1  。
100 zeros,zeros_like       ones ones_like,        0    。
101 empty, empty_like       ,              。
102 eye,identity               N * N    
103 
104 
105         
106 int8,  uint8 - i1, u1                 /    8   
107 int16, uint16 - i2, u2               /    16   
108 int32, uint32 - i4, u4               /    32   
109 int64, uint64 - i8, u8               /    64   
110 float16 - f2                              
111 float32 - f4 or f                            , C float  。
112 float64 - f8 or d                            。 C double Python float  。
113 float128 - f16 or g                        
114 complex64/128/256 -c8/16/32              32 ,64  128         。
115 bool - ?                              True False      
116 object - O                          Python    
117 string_ - S                                   。S10     10    。
118 unicode_ - U                             unicode  
119 
120 
121 NumPy ndarray           
122 123 124 125 
126 NumPy ndarray         
127 128 129     
130 NumPy ndarray      
131     •                     。
132     •            、  (     )    
133     
134 NumPy ndarray         
135     •   /      
136 137     
138 NumPy ndarray           
139     •      I
140     abs, fabs           、          。      ,       fabs。
141     sqrt                     。   arr ** 0.5
142     sqare                   。   arr ** 2
143     exp                   e^x
144     log,log10,             、   10 log、   2 log log(1 + x)。
145     log2,log1p 
146     sign                     :1(  )、0( )、-1(  )。
147     ceil                  ceiling ,            。
148     floor                 floor ,            。
149     
150          II
151     rint                            ,  dtype。
152     modf                                     。
153     isnan                 “    NaN(       )”      
154     isfinite,               “        ( inf, NaN)” “        ”      
155     isinf 
156     cos,                       
157     cosh, 
158     sin, 
159     sinh, 
160     tan, 
161     tanh                 
162     arccos, 
163     arccosh, 
164     arcsin, 
165     arcsinh,
166     arctan, 
167     arctanh
168     logical_not          not x   。   -arr。
169     
170     •      I
171     add                        
172     subtract                          
173     multiply              
174     divide,                  
175     floor_divide 
176     power                     A              B,  A^B。
177     maximum, fmax            。fmax   NaN。
178     minimum, fmin            。fmin   NaN。
179     mod                     
180     
181          II
182     copysign                             
183     greater,                ,         。
184     greater_equal, 
185     less,
186     less_equal,
187     equal, 
188     not_equal
189     logical_and,                ,         。
190     logical_or,
191     logical_xor
192     
193     
194            
195     • NumPy                           (   
196          )。             ,        。
197     •              Python          
198     
199                        
200 201     •  Python  ,     。
202 203     • where where   
204     
205                   
206 207     sum                        。       sum 0。
208     mean             。       mean NaN。
209     std, var             ,     (   n)。
210     min, max           
211     argmin                   
212     cumsum              
213     cumprod             
214 
215 216     • cumsum cumprod   
217     •  axis       
218     
219     
220                      
221     • sum True   
222     • any all       ,        ,   0       True
223     
224              
225 226 227     ---- Error
228     
229                      
230 231     unique(x)             x      ,       。
232     intersect1d(x, y)     x y      ,       。
233     union1d(x, y)         x y   ,       。
234     in1d(x, y)                "x        y"      
235     setdiff1d(x, y)         ,    x    y 
236     setxor1d(x, y)           ,                        。
237     
238          
239 240 241     
242     
243 •    numpy.linalg   I
244     diag                                (       ),           (       0)。
245     dot                     
246     trace                        
247     det                        
248     eig                              
249     inv                        
250 •   numpy.linalg   II
251     pinv                     Moore-Penrose  
252     qr                    QR  
253     svd                        
254     solve                    Ax = b,  A 
255     
256     
257      
258     seed                           
259     permutation                                
260     shuffle                        
261     rand                          
262     randint                             
263     randn                     (    0,    1)
264     binomial                      
265     normal                  (  )      
266     beta                  Beta      
267     chisquare                     
268     gamma                Gamma      
269     uniform                [0, 1]         
270     
271    
272          
273     • reshape    
274     • -1         
275     
276     
277     
278              
279 280     concatenate                ,          
281     vstack, row_stack                 (  0)
282     hstack,                           (  1)
283     column_stack           hstack,                 。
284     dstack                 “  ”          (  2)
285     split                             
286     hsplit,             split      ,     0、 1  2    。
287     vsplit,     
288     dsplit 
289     
290     
291     
292              
293     • _r  
294     • _c  
295 
296             
297     • _tile
298     • _repeat
299 
300               
301     • take
302     • put
303     
304     
305            
306       m × n   X,  X = [x1, x2, ... xn],   i    m   。
307      n × n  ,  Dij = ||xi - xj||2
308 ----------------------------------------------
309 
310 
311 
312 ============================================================================
313 '''
314 #
315 
316 #
317 '''
318 # ============================================================================
319 # Function:  
320 # Explain :         
321 #         :        
322 # ============================================================================
323 '''
324 
325 
326 # ============================================================================
327 '''
328 # ============================================================================
329 #       
330 # ============================================================================
331 '''
332 if __name__ == "__main__":
333     print("123")
334     # # numpy
335     # print(np.arange(10)**2)
336     # # scipy
337     # var_A = np.array([[1,2],[3,4]])
338     # print(linalg.det(var_A))
339     # # pandas
340     # print(pd.Series([1,3,5,np.nan,6,8]))
341     # print(pd.date_range('20130101',periods=3))
342     # dates = pd.date_range('20130101', periods=6)
343     # df = pd.DataFrame(np.random.randn(6, 4), index=dates, columns=list('ABCD'))
344     # print(df)
345     # df1 = df.sort_values(by='B')
346     # print(df1)
347     #
348     # # # mat plot lib
349     # plt.plot([1, 2, 3])
350     # plt.ylabel('some numbers')
351     # plt.show()
352     # # sea born
353     # sns.set(color_codes=True)
354     #
355     # # x = np.random.normal(loc=0.0, scale=1.0,size=100)
356     # # sns.distplot(x)
357 
358 
359     # numpy
360         #
361     # print('          NumPy    ')
362     # data = [6, 7.5, 8, 0, 1]
363     # arr  = np.array(data)
364     # print( arr, arr.dtype )
365     # print( '          NumPy    ')
366     # data = [[1, 2, 3, 4], [5, 6, 7, 8]]
367     # arr = np.array(data)
368     # print( arr, '
: ',arr.shape) #
369 # print(' zeros/empty') 370 # print('
10 0 :
',np.zeros(10)) # 10 0
371 # print('
3*6 :
', np.zeros((3, 6))) # 3*6
372 # print('
2*3*2 , :
',np.empty((2, 3, 2))) # 2*3*2 ,
373 # print('
:
', np.arange(15))
374 # 375 376 377 # print('
:',)
378 # arr = np.array([1, 2, 3], dtype=np.float64) 379 # arr1 = np.array([1, 2, 3], dtype=np.int32) 380 # print( arr.dtype, arr1.dtype ) 381 # print('
astype :', )
382 # int_arr = np.array([1, 2, 3, 4, 5]) 383 # float_arr = int_arr.astype(np.float) 384 # print(int_arr.dtype, float_arr.dtype ) 385 # print('
astype float int :', )
386 # float_arr = np.array([3.7, -1.2, -2.6, 0.5, 12.9, 10.1]) 387 # int_arr = float_arr.astype(dtype=np.int) 388 # print(int_arr) 389 # print('
astype , :')
390 # str_arr = np.array(['1.25', '-9.6', '42'], dtype=np.string_) 391 # float_arr = str_arr.astype(dtype=np.float) 392 # print(float_arr) 393 # print('
astype :')
394 # int_arr = np.arange(10) 395 # float_arr = np.array([.23, 0.270, .357, 0.44, 0.5], dtype=np.float64) 396 # print(int_arr.astype(float_arr.dtype)) 397 # print('
astype , :
',int_arr[0], int_arr[1])
398 # 399 400 401 # print(' / , / 。') 402 # arr = np.array([[1.0, 2.0, 3.0], [4., 5., 6.]]) 403 # print('>>>1
',arr * arr)
404 # print('>>>2
',arr - arr)
405 # print('
:')
406 # arr = np.array([[1.0, 2.0, 3.0], [4., 5., 6.]]) 407 # print('>>>3
', 1 / arr )
408 # print('>>>4
', arr ** 0.5) #
409 # 410 411 412 # print('
')
413 # arr = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) 414 # print(arr[2]) 415 # print(arr[1][2]) 416 # print(arr[1,2]) 417 # print('
')
418 # arr = np.array([[[1, 2, 3], [4, 5, 6]], [[7, 8, 9], [10, 11, 12]]]) 419 # print('>>>1
', arr[0])
420 # print('>>>2
', arr[1, 0])
421 # old_values = arr[0].copy() # arr[0] 422 # arr[0] = 123456 # arr[0] 423 # print('>>>3
', arr)
424 # arr[0] = old_values # 425 # print('>>>4
', arr)
426 # print('
:')
427 # arr = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10]) 428 # print('>>>1
',arr[1:6]) # arr[1] arr[5]
429 # arr = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]]) 430 # print('>>>2
', arr[:2]) # 1、2
431 # print('>>>3
', arr[:2, 1:]) # 1、2 , 2、3
432 # print('>>>4
',arr[:, :1]) #
433 # arr[:2, 1:] = 0 # 1、2 , 2、3 0 434 # print('>>>5
', arr)
435 # 436 437 438 # print(' ') 439 # name_arr = np.array(['Bob', 'Joe', 'Will', 'Bob', 'Will', 'Joe', 'Joe']) 440 # rnd_arr = np_random.randn(7, 4) # 7*4 441 # print('>>>1
', rnd_arr)
442 # print('>>>2
', name_arr == 'Bob') # , 'Bob' True, False。
443 # print('>>>3
', rnd_arr[name_arr == 'Bob']) #
444 # print('>>>4
', rnd_arr[name_arr == 'Bob', :2]) #
445 # print('>>>5
', rnd_arr[~(name_arr == 'Bob')] ) #
446 # mask_arr = (name_arr == 'Bob') | (name_arr == 'Will') 447 # print('>>>6
', rnd_arr[mask_arr]) #
448 # rnd_arr[name_arr != 'Joe'] = 7 449 # print('>>>7
', rnd_arr) # , 7
450 # 451 452 453 # print("
:")
454 # arr = np.empty((8, 4)) 455 # for i in range(8): 456 # arr[i] = i 457 # print('>>>1
', arr)
458 # print('>>>2
', arr[[4, 3, 0, 6]]) # arr[4]、arr[3]、arr[0] arr[6]
459 # print('>>>3
', arr[[-3, -5, -7]]) # arr[3]、arr[5] arr[-7]
460 # arr = np.arange(32).reshape((8, 4)) # reshape 461 # print('>>>4
', arr)
462 # print('>>>5
', arr[[1, 5, 7, 2], [0, 3, 1, 2]]) # arr[1, 0]、arr[5, 3],arr[7, 1] arr[2, 2]
463 # print('>>>6
', arr[[1, 5, 7, 2]][:, [0, 3, 1, 2]]) # 1572 0312
464 # print('>>>7
', arr[np.ix_([1, 5, 7, 2], [0, 3, 1, 2])] ) #
465 # 466 467 468 # print("
")
469 # arr = np.arange(15).reshape((3, 5)) 470 # print('>>>1
', arr)
471 # print('>>>2
', arr.T)
472 # print("
")
473 # arr = np_random.randn(6, 3) 474 # print('>>>3
', np.dot(arr.T, arr))
475 # print("
")
476 # arr = np.arange(16).reshape((2, 2, 4)) 477 # print('>>>4
', arr)
478 # print('>>>5
', arr.transpose((1, 0, 2)))
479 # print('>>>6
', arr.swapaxes(1, 2))
480 # print('>>>7
', arr)
481 # ''' 482 # 483 # arr 484 # - a[0][0] = [0, 1, 2, 3] 485 # - a[0][1] = [4, 5, 6, 7] 486 # - a[1][0] = [8, 9, 10, 11] 487 # - a[1][1] = [12, 13, 14, 15] 488 # transpose , (0, 1, 2, ... , n - 1), 489 # (1, 0, 2) a[x][y][z] = a[y][x][z], 0 1 。 490 # - a'[0][0] = a[0][0] = [0, 1, 2, 3] 491 # - a'[0][1] = a[1][0] = [8, 9, 10, 11] 492 # - a'[1][0] = a[0][1] = [4, 5, 6, 7] 493 # - a'[1][1] = a[1][1] = [12, 13, 14, 15] 494 # ''' 495 # 496 497 # print("
")
498 # arr = np.arange(10) 499 # print('>>>1
', arr)
500 # print('>>>2
', np.sqrt(arr))
501 # print("
")
502 # x = np_random.randn(8) 503 # print(x) 504 # y = np_random.randn(8) 505 # print(y) 506 # print('>>>3
', np.maximum(x, y))
507 # print("
modf ")
508 # arr = np_random.randn(7) * 5 # 5 509 # print('>>>4
', np.modf(arr))
510 # 511 512 513 # points = np.arange(-10, 10, 0.005) # 100 514 # xs, ys = np.meshgrid(points, points) # xs, ys 515 # # print('>>>1
', xs, ys)
516 # z = np.sqrt(xs ** 2 + ys ** 2) 517 # # print (z) 518 # print("
")
519 # plt.imshow(z, cmap = plt.cm.gray)#gray 520 # plt.colorbar() 521 # # plt.title("Image plot of $\sqrt{x^2 + y^2}$ for a grid of values") 522 # pylab.show() 523 # 524 525 526 # ''' 527 # zip ,zip , 1 tuple 。 528 # zip([1, 2, 3], [4, 5, 6], [7, 8, 9]) 529 # :[(1, 4, 7), (2, 5, 8), (3, 6, 9)] 530 # ''' 531 # print("
")
532 # x_arr = np.array([1.1, 1.2, 1.3, 1.4, 1.5]) 533 # y_arr = np.array([2.1, 2.2, 2.3, 2.4, 2.5]) 534 # cond = np.array([True, False, True, True, False]) 535 # result = [(x if c else y) for x, y, c in zip(x_arr, y_arr, cond)] # 536 # print('>>>1
', result)
537 # print('>>>2
', np.where(cond, x_arr, y_arr)) # NumPy where
538 # arr = np_random.randn(4, 4) 539 # print('>>>3
', arr)
540 # print('>>>4
', np.where(arr > 0, 2, -2))
541 # print('>>>5
', np.where(arr > 0, 2, arr))
542 # print("
where ")
543 # cond_1 = np.array([True, False, True, True, False]) 544 # cond_2 = np.array([False, True, False, True, False]) 545 # result = [] 546 # for i in range(len(cond)): 547 # if cond_1[i] and cond_2[i]: 548 # result.append(0) 549 # elif cond_1[i]: 550 # result.append(1) 551 # elif cond_2[i]: 552 # result.append(2) 553 # else: 554 # result.append(3) 555 # print('>>>6
', result)
556 # result = np.where(cond_1 & cond_2, 0,np.where(cond_1, 1, np.where(cond_2, 2, 3))) 557 # print('>>>7
', result)
558 # 559 560 # print("
, :")
561 # arr = np.random.randn(5, 5) 562 # print('>>>1
', arr)
563 # print('>>>2
', arr.mean()) #
564 # print('>>>3
', arr.sum()) #
565 # print('>>>4
', arr.mean(axis=1)) #
566 # print('>>>5
', arr.sum(0)) # ,axis
567 # ''' 568 # cumsum: 569 # - :a[i][j] += a[i - 1][j] 570 # - :a[i][j] *= a[i][j - 1] 571 # cumprod: 572 # - :a[i][j] += a[i - 1][j] 573 # - :a[i][j] *= a[i][j - 1] 574 # ''' 575 # print("
cunsum cumprod ")
576 # arr = np.array([[0, 1, 2], [3, 4, 5], [6, 7, 8]]) 577 # print('>>>6
', arr.cumsum(1))
578 # print('>>>7
', arr.cumprod(1))
579 # print('>>>8
', arr)
580 # print('>>>9
', arr.cumsum(0))
581 # 582 583 584 # print("
")
585 # arr = np_random.randn(100) 586 # print((arr > 0).sum()) 587 # print("
")
588 # bools = np.array([False, False, True, False]) 589 # print( bools.any()) # True True 590 # print( bools.all()) # False False 591 # 592 593 594 # print("
")
595 # arr = np_random.randn(20) 596 # arr1 = arr.sort() 597 # print('>>>1
', arr1)
598 # print("
")
599 # arr = np_random.randn(5, 5) 600 # arr2 = arr.sort(1) 601 # print('>>>3
', arr2) #
602 # arr3 = arr.sort(0) 603 # print('>>>4
', arr3)
604 # print("
5% ")
605 # large_arr = np_random.randn(1000) 606 # large_arr.sort() 607 # print('>>>5
', large_arr[int(0.05 * len(large_arr))])
608 # 609 610 # print( '
unique ')
611 # names = np.array(['Bob', 'Joe', 'Will', 'Bob', 'Will', 'Joe', 'Joe']) 612 # print('>>>1
', sorted(set(names))) # Python
613 # print('>>>2
', np.unique(names))
614 # ints = np.array([3, 3, 3, 2, 2, 1, 1, 4, 4]) 615 # print('>>>3
', np.unique(ints))
616 # print('
')
617 # values = np.array([6, 0, 0, 3, 2, 5, 6]) 618 # print('>>>4
', np.in1d(values, [2, 3, 6]))
619 # 620 621 # test 622 # print( '
: ')
623 # arr = np.arange(10) 624 # np.save('test_some_array', arr) 625 # print(np.load('test_some_array.npy')) 626 # print( '
')
627 # np.savez('test_array_archive.npz', a=arr, b=arr) 628 # arch = np.load('test_array_archive.npz') 629 # print(arch['b']) 630 # # 631 # print('
csv ')
632 # arr = np.loadtxt('array_ex.txt', delimiter=',') 633 # print(arr) 634 # 635 636 # print( '
')
637 # x = np.array([[1., 2., 3.], [4., 5., 6.]]) 638 # y = np.array([[6., 23.], [-1, 7], [8, 9]]) 639 # print('>>>1
', x.dot(y)) #
640 # print('>>>2
', np.dot(x, np.ones(3)))
641 # x = np_random.randn(5, 5) 642 # print('>>>3
', x)
643 # print(' ') 644 # mat = x.T.dot(x) 645 # print( '>>>4
', inv(mat)) #
646 # print( '>>>5
', mat.dot(inv(mat))) # , 。
647 # print( ' ') 648 # print('>>>6
', mat)
649 # q, r = qr(mat) 650 # print('>>>7
', q)
651 # print('>>>8
', r)
652 # 653 654 # print("
:")
655 # samples = np.random.normal(size=(5, 5)) 656 # print('>>>1
', samples)
657 # print("
0 1 ")
658 # N = 10 659 # print([normalvariate(0, 10)for _ in range(N)]) 660 # print(np.random.normal(size=N)) # 661 # 662 663 664 # print("
")
665 # arr = np.arange(8) 666 # print('>>>1
', arr.reshape((4, 2)))
667 # print('>>>2
', arr.reshape((4, 2)).reshape((2, 4))) #
668 # print("
")
669 # arr = np.arange(54) 670 # print('>>>3
', arr.reshape((9, -1)))
671 # print("
")
672 # other_arr = np.ones((6, 9)) 673 # print('>>>4
', other_arr.shape)
674 # print('>>>5
', arr.reshape(other_arr.shape))
675 # print("
")
676 # arr = np.arange(15).reshape((5, 3)) 677 # print('>>>6
', arr.ravel())
678 # 679 680 681 # print("
")
682 # print("
")
683 # arr1 = np.array([[1, 2, 3], [4, 5, 6]]) 684 # arr2 = np.array([[7, 8, 9], [10, 11, 12]]) 685 # print('>>>1
', np.concatenate([arr1, arr2], axis=0)) #
686 # print('>>>2
', np.concatenate([arr1, arr2], axis=1)) #
687 # print("
stack stack")
688 # print('>>>3
', np.vstack((arr1, arr2))) #
689 # print('>>>4
', np.hstack((arr1, arr2)) ) #
690 # print("
")
691 # arr = np_random.randn(5, 5) 692 # print("
")
693 # first, second, third = np.split(arr, [1, 3], axis=0) 694 # print('>>>5
', first)
695 # print('>>>6
', second)
696 # print('>>>7
', third)
697 # print("
")
698 # first, second, third = np.split(arr, [1, 3], axis=1) 699 # print('>>>8
', first)
700 # print('>>>9
', second)
701 # print('>>>10
', third)
702 # print("
")
703 # arr = np.arange(6) 704 # arr1 = arr.reshape((3, 2)) 705 # arr2 = np_random.randn(3, 2) 706 # print("
r_ ")
707 # print('>>>11
', np.r_[arr1, arr2])
708 # print("
c_ ")
709 # print('>>>12
', np.c_[np.r_[arr1, arr2], arr])
710 # print('
')
711 # print('>>>13
', np.c_[1:6, -10:-5])
712 # 713 # try: 714 # print("
")
715 # print("
Repeat: ")
716 # arr = np.arange(4) 717 # print('>>>1
', arr.repeat([1, 2, 3, 4])) # 3 , 2, 3, 4 。
718 # print("
Repeat, ")
719 # arr = np_random.randn(3, 3) 720 # print('>>>2
', arr)
721 # print('>>>3
', arr.repeat(2, axis=0)) # repeat
722 # print('>>>4
', arr.repeat(2, axis=1)) # repeat
723 # print('>>>5
', arr.repeat(2, axis=0)) # repeat
724 # print("
Tile: ")
725 # arr = np_random.randn(2, 2) 726 # print('>>>6
', np.tile(arr, 2))
727 # print('>>>7
', np.tile(arr, (2, 3)) ) # tile
728 # except Exception: 729 # print(" !!!") 730 731 # try: 732 # print("
Fancy Indexing ")
733 # arr = np.arange(10) * 100 734 # print(arr) 735 # inds = [7, 1, 2, 6] 736 # print('>>>1
', arr[inds])
737 # print("
take")
738 # print('>>>2
', arr.take(inds))
739 # print("
put ")
740 # print('>>>3
', arr.put(inds, 50))
741 # print('>>>4
', arr)
742 # print('>>>5
', arr.put(inds, [70, 10, 20, 60]))
743 # print('>>>6
', arr)
744 # print("
take ")
745 # arr = np_random.randn(2, 4) 746 # inds = [2, 0, 2, 1] 747 # print('>>>7
', arr)
748 # print('>>>8
', arr.take(inds, axis=1))
749 # except Exception: 750 # print(" !!!") 751 752 753 try: 754 print("
:
") 755 nsteps = 1000 756 draws = np.random.randint(0, 2, size=nsteps) 757 steps = np.where(draws > 0, 1, -1) 758 walk = steps.cumsum() 759 print(" ") 760 plt.title('Random Walk') 761 limit = max(abs(min(walk)), abs(max(walk))) 762 plt.axis([0, nsteps, -limit, limit]) 763 x = np.linspace(0, nsteps, nsteps) 764 plt.plot(x, walk, 'g-') 765 plt.show() 766 except Exception: 767 print(" !!!") 768 # print('>>>1
', )
769 # print('>>>2
', )
770 # print('>>>3
', )
771 # print('>>>4
', )
772 # print('>>>5
', )
773 # print('>>>6
', )
774 # print('>>>7
', )
775 # print('>>>8
', )
776 # print('>>>9
', )

 
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転載先:https://www.cnblogs.com/caochucheng/p/10034018.html