format string The Format function

Grammar

It replaces% with {} and:.

The format output string in Python uses the format () function, the string is the class , you can use the method;

Python is a fully object-oriented language, and everything is an object;

The parameters of the string are represented by {NUM} ,0, representing the first parameter ,1, representing the second parameter , and then sequentially sliding scale;

Use ":"to specify the actions required to represent the element, such as ":. 3", three decimal Places, ": 8" for 8 character spaces, etc.;

You can also add specific letters , such as:

' B ' -binary. The number is output as a base of 2.

' C '-character. Converts an integer to the corresponding Unicode string before printing.

' d ' -decimal integer. The number is output as a base of 10.

' O '-eight binary. The number is output as a base of 8.

' x '-16 binary. The number is output in 16, and the number of digits above 9 is in lowercase letters.

The ' E ' -power symbol. Use scientific notation to print numbers, and ' e ' for power.

' G '-general format. The value is output in fixed-point format. When the number is particularly large, it is printed in a power form.

' N '-number. When the value is an integer and ' d ', the values are the same as the ' G ' when they are floating-point numbers. The difference is that it inserts a numeric delimiter according to the locale.

'% '-hundred fractions. Multiply the value by 100 and then print in fixed-point (' F ') format, followed by a percent semicolon.

Number (0, 1, ...) Represents the elements inside the format (), so you can use the "." method of invoking the element;

See URL: http://www.python.org/dev/peps/pep-3101/

The code is as follows:

1 #-*-coding:utf-8-*-2 3Age = 254Name ='Caroline'5 6 Print('{0} is {1} years.'. Format (name, age))#Output Parameters7 Print('{0} is a girl.'. Format (name))8 Print('{0:.3} is a decimal.'. Format (1/3))#three digits after the decimal point9 Print('{0:_^11} is a one-length.'. Format (name))#use _ to empty the spaceTen Print('{First} is as {second}.'. Format (First=name, second='Wendy'))#alias Substitution One Print('My name is {0.name}'. Format (Open ('OUT.txt','W')))#Calling Methods A Print('My name is {0:8}.'. Format ('Fred'))#Specify width

Output:

1   is 2is 3 are 4 is a 11    5 is 6 are OUT.txt 7 is Fred    .

Format string The Format function