Python print函数用法，print 格式化输出
原文地址：http://blog.csdn.net/zanfeng/article/details/52164124 / https://www.cnblogs.com/hokky/p/8434236.html
使用print输出各型的
- 字符串
- 整数
- 浮点数
- 出度及精度控制
1 2 3 4 | strHello = ‘Hello Python‘print strHello#输出结果：Hello Python#直接出字符串 |
python print也支持参数格式化，与C言的printf似，
1 2 3 | strHello = "the length of (%s) is %d" %(‘Hello World‘,len(‘Hello World‘))print strHello#输出果：the length of (Hello World) is 11 |
1 2 3 4 5 6 7 8 9 | nHex = 0x20#%x --- hex 十六进制#%d --- dec 十进制#%d --- oct 八进制 print "nHex = %x,nDec = %d,nOct = %o" %(nHex,nHex,nHex) #输出结果：nHex = 20,nDec = 32,nOct = 40#使用整数的各个制打印同一个数 |
如果需要输出二进制的话，可以使用python函数 bin()
1 2 3 4 5 6 | Python 2.7.6 (default, Nov 10 2013, 19:24:18) [MSC v.1500 32 bit (Intel)] on win32Type "help", "copyright", "credits" or "license" for more information.>>> bin(789)‘0b1100010101‘>>> |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 | import math#defaultprint "PI = %f" % math.pi#width = 10,precise = 3,align = leftprint "PI = %10.3f" % math.pi#width = 10,precise = 3,align = rigthprint "PI = %-10.3f" % math.pi#前面填充字符print "PI = %06d" % int(math.pi) #输出结果#PI = 3.141593#PI = 3.142#PI = 3.142#PI = 000003#浮点数的格式化，精度、度和 |
1 2 3 4 5 6 7 8 9 10 11 | #precise = 3print "%.3s " % ("jcodeer")#precise = 4print "%.*s" % (4,"jcodeer")#width = 10,precise = 3print "%10.3s" % ("jcodeer")#输出结果：#jco#jcod# jco#同于字符串也存在精度、度和。 |
1 2 3 4 5 6 7 8 9 | l = [1,2,3,4,‘jcodeer‘]print l#输出结果：[1, 2, 3, 4, ‘jcodeer‘]#于list直接打印即可‘‘‘6.出字典(dictionary)‘‘‘d = {1:‘A‘,2:‘B‘,3:‘C‘,4:‘D‘}print d#输出结果：{1: ‘A‘, 2: ‘B‘, 3: ‘C‘, 4: ‘D‘}#同python也是支持dictionary出的 |
print 会自动在行末加上回车,如果不需回车，只需在print语句的结尾添加一个逗号”,“，就可以改变它的行为。
1 2 | for i in range(0,5): print i, |
或直接使用下面的函数进行输出：
1 | sys.stdout.write("输出的字串") |
有个同事问我python里面print ”%r” 是什么用途，被问倒了。
用了这么些年的python，还没用过print %r。
网上查了一下，发现%r是一个万能的格式付，它会将后面给的参数原样打印出来，带有类型信息。
1 2 3 4 5 6 7 8 9 10 11 12 | formatter = "%r %r %r %r" print formatter % (1, 2, 3, 4)print formatter % ("one", "two", "three", "four")print formatter % (True, False, False, True)print formatter % (formatter, formatter, formatter, formatter)print formatter % ("I had this thing.","That you could type up right.", "But it didn‘t sing.", "So I said goodnight." ) |
输出结果：
1 2 3 4 5 6 7 | $ python ex8.py1 2 3 4‘one‘ ‘two‘ ‘three‘ ‘four‘True False False True‘%r %r %r %r‘ ‘%r %r %r %r‘ ‘%r %r %r %r‘ ‘%r %r %r %r‘‘I had this thing.‘ ‘That you could type up right.‘ "But it didn‘t sing." ‘So I said goodnight.‘$ |