Differences between formatted string% and format two methods in Python

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Python2.6 introduced a format formatted string method, now there are two ways to format the string, that is,% and format, what is the difference between the two methods? Please see the following resolution.

# define a coordinate value c = (+)#  use% to format " enemy Coordinates:%s" % c

The above code obviously throws a typeerror like this:

Typeerror:not all arguments converted during string formatting

Like this kind of formatting needs we need to write the following ugly format:

# define a coordinate value c = (+)#  Use the% ugly formatting ... " enemy Coordinates:%s " % (c,)

There is no problem with format:

# define a coordinate value c = (in.)# format " Enemy Coordinates: {}" using format  . Format (c)

In general, using% is sufficient to meet our needs, but it is best to choose the format method if you want to add elements or list types to a location like this.

New features

Added f-strings to Python3.6:

" Q1mi " in[2]: Age =in[3]: F'My name is {name}. I ' m {age}"out["My name is Q1mi.i ' m "

Common methods for format

By Location (index)

IN[1]: data = ["q1mi",]in["name:{0}, age:{1}". Format (*data) out['name:q1mi, age:18'

by keyword

IN[1]: data = {"name""Q1mi" "Age" :}in["name:{name}, age:{age}". Format (* *data) out['  name:q1mi, age:18'

Through object properties

IN[1]:classPerson (Object): ...:def __init__(self, Name, age): ...: Self.name=name ...: self.age=Age ...:def __str__(self): ...:return "This was {self.name}, {self.age}, years old.". Format (self=Self ) ...: in[2]: p = person ("Q1mi", 18) in[3]: str (p) out[3]:'This was q1mi, years old.'

by subscript

" {0[0]} is {0[1]} years old. " . Format (data) out['q1mi is the years old. '

Fill and align

Padding is used in conjunction with alignment

^ < > is centered, left-aligned, right-aligned, followed by width.

: The filled character after the number, only one character, not specified by default is filled with spaces.

IN[1]:"{: >10}". Format (' -') out[0][' -'in[2]:"{: 0>10}". Format (' -') out[2]:'0000000018'in[3]:"{: a>10}". Format (' -') out[3]:'AAAAAAAA18

Add a string that comes with the Zfill () method:

The Python Zfill () method returns a string of the specified length, the original string is right-aligned, and the front padding is 0.

Zfill () method Syntax: Str.zfill (width)

Parameter width Specifies the length of the string. Original string right-aligned, front padding 0

Returns a string of the specified length

" {:. 2f} ". Format (3.1415926) out['3.14'

Accuracy and type F

Accuracy is often used in conjunction with Type F.

" {:. 2f} ". Format (3.1415926) out['3.14'

Where. 2 represents a precision of 2 length, and F represents a float type.

Other binary

b d o x are binary, decimal, octal, hexadecimal, respectively.

IN[1]:"{: b}". Format (18) out[0]['10010'in[2]:"{:D}". Format (18) out[2]:' -'in[3]:"{: o}". Format (18) out[3]:' A'in[4]:"{: x}". Format (18) out[4]:' A'

Thousands separator

" {:,} ". Format (1234567890) out['1,234,567,890'

Differences between formatted string% and format two methods in Python