Python學習：print函數的用法

1. 輸出字元串

>>> strHello = 'Hello World' 

>>> print (strHello)

Hello World      

2. 格式化輸出整數

支援參數格式化，與C語言的printf類似

>>> strHello = "the length of (%s) is %d" %('Hello World',len('Hello World'))

>>> print (strHello)
the length of (Hello World) is 11      

3. 格式化輸出16進制，十進制，八進制整數

#%x --- hex 十六進制
#%d --- dec 十進制
#%o --- oct 八進制
 
>>> nHex = 0xFF
>>> print("nHex = %x,nDec = %d,nOct = %o" %(nHex,nHex,nHex))
nHex = ff,nDec = 255,nOct = 377      

4.格式化輸出浮點數(float)

import math
>>> print('PI=%f'%math.pi)
PI=3.141593
>>> print ("PI = %10.3f" % math.pi)

PI =      3.142
>>> print ("PI = %-10.3f" % math.pi)

PI = 3.142     
>>> print ("PI = %06d" % int(math.pi))
PI = 000003      

5. 格式化輸出浮點數(float)

>>> precise = 3
>>> print ("%.3s " % ("python"))
pyt

>>> precise = 4
>>> print ("%.*s" % (4,"python"))//*号用後面的int數字代替,又如"%*.2s"等等，變量控制
pyth

>>> print ("%10.3s " % ("python"))
       pyt      

6.輸出清單(List)

輸出清單

>>> lst = [1,2,3,4,'python']
>>> print (lst)
[1, 2, 3, 4, 'python']      

輸出字典

>>> d = {1:'A',2:'B',3:'C',4:'D'}
>>> print(d)
{1: 'A', 2: 'B', 3: 'C', 4: 'D'}      

7. 自動換行

>>> for i in range(0,6):
    print (i,)

    
0
1
2
3
4
5      

>>> import sys
>>> sys.stdout.write('Hello World')
Hello World