python format

format语法

基本插入语法

# default arguments
print("Hello {}, your balance is {}.".format("Adam", 230.2346))

# positional arguments
print("Hello {0}, your balance is {1}.".format("Adam", 230.2346))

# keyword arguments
print("Hello {name}, your balance is {blc}.".format(name="Adam", blc=230.2346))

# mixed arguments
print("Hello {0}, your balance is {blc}.".format("Adam", blc=230.2346)

输入字符格式化

类型	意义
d	整型
c	字符
b	二进制
o	十进制
x	十六进制小写字母
X	十六进制大写字母
%	百分数，放置%在其后
f	浮点数，默认精度为6
e	科学计数法（小写e表示）
E	科学计数法（大写E表示）

文本对齐

类型	意义
<	向左对齐
>	右向对齐
=	符号位于最左
^	居中对齐

# integer numbers with right alignment
print("{:5d}".format(12))

# float numbers with center alignment
print("{:^10.3f}".format(12.2346))

# integer left alignment filled with zeros
print("{:<05d}".format(12))

# float numbers with center alignment
print("{:=8.3f}".format(-12.2346))

   12
  12.235  
12000
- 12.235

动态格式化

# dynamic string format template
string = "{:{fill}{align}{width}}"

# passing format codes as arguments
print(string.format('cat', fill='*', align='^', width=5))

# dynamic float format template
num = "{:{align}{width}.{precision}f}"

# passing format codes as arguments
print(num.format(123.236, align='<', width=8, precision=2))

**cat**
123.24