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random Ä£¿é°üº¬Ðí¶àËæ»úÊýÉú³ÉÆ÷. »ù±¾Ëæ»úÊýÉú³ÉÆ÷(»ùÓÚ Wichmann ºÍ Hill , 1982 µÄÊýѧÔËËãÀíÂÛ) ¿ÉÒÔͨ¹ýºÜ¶à·½·¨·ÃÎÊ, Èç Example 2-29 Ëùʾ. 2.17.0.1. Example 2-29. ʹÓà random Ä£¿é»ñµÃËæ»úÊý×Ö File: random-example-1.py import random for i i
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random Ä£¿é°üº¬Ðí¶àËæ»úÊýÉú³ÉÆ÷.
»ù±¾Ëæ»úÊýÉú³ÉÆ÷(»ùÓÚ Wichmann ºÍ Hill , 1982 µÄÊýѧÔËËãÀíÂÛ) ¿ÉÒÔͨ¹ýºÜ¶à·½·¨·ÃÎÊ, Èç Example 2-29 Ëùʾ.
2.17.0.1. Example 2-29. ʹÓà random Ä£¿é»ñµÃËæ»úÊý×Ö
File: random-example-1.py
import random
for i in range(5):
# random float: 0.0 <= number < 1.0
print random.random(),
# random float: 10 <= number < 20
print random.uniform(10, 20),
# random integer: 100 <= number <= 1000
print random.randint(100, 1000),
# random integer: even numbers in 100 <= number < 1000
print random.randrange(100, 1000, 2)
0.946842713956 19.5910069381 709 172
0.573613195398 16.2758417025 407 120
0.363241598013 16.8079747714 916 580
0.602115173978 18.386796935 531 774
0.526767588533 18.0783794596 223 344
×¢ÒâÕâÀïµÄ randint º¯Êý¿ÉÒÔ·µ»ØÉϽç, ¶øÆäËûº¯Êý×ÜÊÇ·µ»ØÐ¡ÓÚÉϽçµÄÖµ. ËùÓк¯Êý¶¼ÓпÉÄÜ·µ»ØÏ½çÖµ.
Example 2-30 չʾÁË choice º¯Êý, ËüÓÃÀ´´ÓÒ»¸öÐòÁÐÀï·Ö¼ð³öÒ»¸öËæ»úÏîÄ¿. Ëü¿ÉÒÔÓÃÓÚÁбí, Ôª×é, ÒÔ¼°ÆäËûÐòÁÐ(µ±È», ·Ç¿ÕµÄ).
2.17.0.2. Example 2-30. ʹÓà random Ä£¿é´ÓÐòÁÐÈ¡³öËæ»úÏî
File: random-example-2.py
import random
# random choice from a list
for i in range(5):
print random.choice([1, 2, 3, 5, 9])
2
3
1
9
1
ÔÚ 2.0 ¼°ÒÔºó°æ±¾, shuffle º¯Êý¿ÉÒÔÓÃÓÚ´òÂÒÒ»¸öÁбíµÄÄÚÈÝ (Ò²¾ÍÊÇÉú³ÉÒ»¸ö¸ÃÁбíµÄËæ»úÈ«ÅÅÁÐ). Example 2-31 չʾÁËÈçºÎÔھɰ汾ÖÐʵÏָú¯Êý.
2.17.0.3. Example 2-31. ʹÓà random Ä£¿é´òÂÒÒ»¸±ÅÆ
File: random-example-4.py
import random
try:
# available in 2.0 and later
shuffle = random.shuffle
except AttributeError:
def shuffle(x):
for i in xrange(len(x)-1, 0, -1):
# pick an element in x[:i+1] with which to exchange x[i]
j = int(random.random() * (i
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