python string formatted string formatting python

python string formatting

 

Python string formatting in two ways:% formatter mode, format mode

% Formatter

%[(name)][flags][width].[precision]typecode

• (Name) Alternatively, for selecting a specified key
• flags optional, alternative values ​​are:
  • + Right aligned; added just before the positive, negative numbers preceded by a minus sign;
  • - Left; unsigned positive front, a minus sign before the negative;
  • Right-aligned spaces; spaces, a minus sign before the negative before positive number;
  • Align Right 0; unsigned before positive and negative numbers preceded by a minus sign; the space filled with 0
• width optional, possession of width
• .precision optional decimal places reserved
• typecode Required
  
  • s, __str__ method of obtaining the return value of the incoming object and is formatted to the specified position
  • r, __repr__ method of obtaining the return value of the incoming object and is formatted to the specified position
  • C, integers: a number into its corresponding unicode values, decimal range 0 <= i <= 1114111 (py27 only supports 0-255); character: adding a character to the specified position
  • O, the octal notation is converted into an integer, and formats it into the designated location
  • x, an integer converted into hexadecimal notation, and formats it into the designated location
  • d, convert integer, floating point decimal representation and formats it to a designated position
  • E, integer, floating-point numbers into scientific notation, and formats it into the designated location (lowercase e)
  • E, converting the integer, floating-point number in scientific notation, and formats it to the specified position (uppercase E)
  • F, converting integers, floating point numbers to floating point representation and formats it to the specified position (after the default 6 decimal places)
  • F, ibid.
  • g, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
  • G, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
  • %, When the flag is present formatted string, a percent sign indicates required by %%

Note: Python the percent format is automatically converted into a binary representation of an integer as not exist

(Name) Alternatively, for selecting a specified key

 

a = "%(name)s-----%(age)d "%{'name':'xx','age':20}
print(a)

 

Results of the:

xx-----20

flags optional, alternative values ​​are:

• + Right aligned; added just before the positive, negative numbers preceded by a minus sign;
• - Left; unsigned positive front, a minus sign before the negative;
• Right-aligned spaces; spaces, a minus sign before the negative before positive number;
• Align Right 0; unsigned before positive and negative numbers preceded by a minus sign; the space filled with 0

width optional, possession of width

account name 10, +, right justified, age accounted for 10, -, Left

b = "%(name)+10s————————%(age)-10d————————"%{'name':'xx','age':20}
print(b)

Results of the:

        xx————————20        ————————

 Space, right-aligned

 0, the space is filled with 0

c = "------%(year) d******%(age)010d "%{'year':2016,'age':-20}
print(c)

Results of the:

------ 2016******-000000020 

.precision optional decimal places reserved

Only two decimal places

d = '--------%(p).2f'%{'p':1.23456}
d1 = '--------%(p)f'%{'p':1.23456}
print(d)
print(d1)

Results of the:

--------1.23
--------1.234560

typecode Required

• C, integers: a number into its corresponding unicode values, decimal range 0 <= i <= 1114111 (py27 only supports 0-255); character: adding a character to the specified position
• O, the octal notation is converted into an integer, and formats it into the designated location
• x, an integer converted into hexadecimal notation, and formats it into the designated location

e = 'c *** ***%%% *** the x'% (65,15,15)
print (e)

Results of the:

***A***17***f

• E, integer, floating-point numbers into scientific notation, and formats it into the designated location (lowercase e)
• E, converting the integer, floating-point number in scientific notation, and formats it to the specified position (uppercase E)

f = '-----% (num) ------% of (whether) E'% { 'or' 1000000000}
print(f)

Results of the:

-----1.000000e+09------1.000000E+09

• g, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
• G, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)

g '-----% (num) g ------% (num1) G'% { 'whether', 1000000000, 'num1': 100}
print(g)

Results of the:

-----1e+09------100

• %, When the format string flag is present, it is necessary %% represented by a percent sign (similar to turn back effect)

s = 'aaa %'
print(s)
s1 = 'aaa %s %%'%('bbb')
print(s1)

Results of the:

aaa %
aaa bbb% 

format mode

Defined digital format to: Start Number '. I met ':' characters know you want to define a number of display formats. Defined as sequential format 

[[fill]align][sign][#][0][width][,][.precision][type]

• [Optional] fill the space filled with character
• [optional] align alignment (in conjunction with the use of width)
• <, Left-aligned content
• > Contents in the right alignment (default)
• = Contents in the right alignment, the symbol on the left pad characters, and only valid digital type. Even: digital sign + filler +
• ^, Centered content
• sign [optional] whether the symbol numbers
  • +, Positive plus plus plus minus minus sign;
  •  - a positive sign change, plus minus negative sign;
  • Plus negative space, plus space, negative sign;
• # [Optional] For binary, octal, hexadecimal, if coupled with # displayed 0b / 0o / 0x, or do not show
• , [Optional] is added to a digital separators, such as: 1,000,000
• [optional] format bit width occupied by the width
• .precision [optional] decimal place precision reserved
• type [optional] format type
  • Incoming "string type" parameter
    • s, string type data format
    • Blank, unspecified type, the default is None, with s
  • Incoming "integer type" parameter
    
    • b, will be automatically converted to decimal integer of 2 hexadecimal format then
    • c, will automatically convert a decimal integer to its corresponding unicode character
    • d, decimal integer
    • o, it will be automatically converted to decimal integer octal and format;
    • x, the decimal integer automatically converted into a hexadecimal format and (lower case x)
    • X, will be automatically converted to decimal integer in hexadecimal format and then (upper case X)
  • Passed "or decimal floating-point type" parameter
    • E, is converted to scientific notation (lowercase e) shows, then format;
    • E, is converted to scientific notation (uppercase E), and format;
    • F, is converted to floating point (the default after the decimal point 6) shows, then format;
    • F., Is converted to floating point (the default after the decimal point 6) shows, then format;
    • g, e and f are automatically switched
    • G, automatically switches E and F
    • %, Shows the percentage (default display 6 decimal place)

 

[Optional] fill the space filled with character

[optional] align alignment (in conjunction with the use of width)

• <, Left-aligned content
• > Contents in the right alignment (default)
• = Contents in the right alignment, the symbol on the left pad characters, and only valid digital type. Even: digital sign + filler +
• ^, Centered content

[optional] format bit width occupied by the width

s1 ='---{:*^20s}----'.format('welcome')
print(s1)
s2 ='---{:*>20s}----'.format('welcome')
print(s2)
s3 ='---{:*<20s}----'.format('welcome')
print(s3)

Results of the:

---******welcome*******----
---*************welcome----
---welcome*************----

# [Optional] For binary, octal, hexadecimal, if coupled with # displayed 0b / 0o / 0x, or do not show

• b, will be automatically converted to decimal integer of 2 hexadecimal format then
• c, will automatically convert a decimal integer to its corresponding unicode character
• d, decimal integer
• o, it will be automatically converted to decimal integer octal and format;
• x, the decimal integer automatically converted into a hexadecimal format and (lower case x)
• X, will be automatically converted to decimal integer in hexadecimal format and then (upper case X)

Three methods of representation

a1 = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%},{:c}".format(15, 15, 15, 15, 15, 15.87623,65)
a2 = "numbers: {0:b},{0:o},{0:d},{0:x},{0:X}, {0:%},{1:c}".format(15,65)
A3 = "numbers: {Surely, b}, {whether: o}, {Surely, d}, {whether x}, {Surely, 10}, {num%}, {c, c}". format ( Surely = 15, C = 65)
print(a1)
print(a2)
print(a3)

Results of the:

numbers: 1111,17,15,f,F, 1587.623000%,A
numbers: 1111,17,15,f,F, 1500.000000%,A
numbers: 1111,17,15,f,F, 1500.000000%,A

, [Optional] is added to a digital separators, such as: 1,000,000

.precision [optional] decimal place precision reserved

n = '{---} ---- :, d. size (10000000)
n1 = '--- {:. 2f} ----'. format (1.2345)
print(n)
print(n1)

Results of the:

---10,000,000----
---1.23----

 format commonly used format

tp1 = "i am {}, age {}, {}".format("seven", 18, 'alex')
tp2 = "i am {}, age {}, {}".format(*["seven", 18, 'alex'])
tp3 = "i am {0}, age {1}, really {0}".format("seven", 18)
tp4 = "i am {0}, age {1}, really {0}".format(*["seven", 18])
tp5 = "i am {name}, age {age}, really {name}".format(name="seven", age=18)
tp6 = "i am {name}, age {age}, really {name}".format(**{"name": "seven", "age": 18})
tp7 = "i am {0[0]}, age {0[1]}, really {0[2]}".format([1, 2, 3], [11, 22, 33])
tp8 = "i am {:s}, age {:d}, money {:f}".format("seven", 18, 88888.1)
tp9 = "i am {:s}, age {:d}".format(*["seven", 18])
tp10 = "i am {name:s}, age {age:d}".format(name="seven", age=18)
tp11 = "i am {name:s}, age {age:d}".format(**{"name": "seven", "age": 18})
print(tp1)
print(tp2)
print(tp3)
print(tp4)
print(tp5)
print(tp6)
print(tp7)
print(tp8)
print(tp9)
print(tp10)
print(tp11)

Results of the:

i am seven, age 18, alex
i am seven, age 18, alex
i am seven, age 18, really seven
i am seven, age 18, really seven
i am seven, age 18, really seven
i am seven, age 18, really seven
i am 1, age 2, really 3
i am seven, age 18, money 88888.100000
i am seven, age 18
i am seven, age 18
i am seven, age 18

Python string formatting in two ways:% formatter mode, format mode

% Formatter

%[(name)][flags][width].[precision]typecode

• (Name) Alternatively, for selecting a specified key
• flags optional, alternative values ​​are:
  • + Right aligned; added just before the positive, negative numbers preceded by a minus sign;
  • - Left; unsigned positive front, a minus sign before the negative;
  • Right-aligned spaces; spaces, a minus sign before the negative before positive number;
  • Align Right 0; unsigned before positive and negative numbers preceded by a minus sign; the space filled with 0
• width optional, possession of width
• .precision optional decimal places reserved
• typecode Required
  
  • s, __str__ method of obtaining the return value of the incoming object and is formatted to the specified position
  • r, __repr__ method of obtaining the return value of the incoming object and is formatted to the specified position
  • C, integers: a number into its corresponding unicode values, decimal range 0 <= i <= 1114111 (py27 only supports 0-255); character: adding a character to the specified position
  • O, the octal notation is converted into an integer, and formats it into the designated location
  • x, an integer converted into hexadecimal notation, and formats it into the designated location
  • d, convert integer, floating point decimal representation and formats it to a designated position
  • E, integer, floating-point numbers into scientific notation, and formats it into the designated location (lowercase e)
  • E, converting the integer, floating-point number in scientific notation, and formats it to the specified position (uppercase E)
  • F, converting integers, floating point numbers to floating point representation and formats it to the specified position (after the default 6 decimal places)
  • F, ibid.
  • g, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
  • G, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
  • %, When the flag is present formatted string, a percent sign indicates required by %%

Note: Python the percent format is automatically converted into a binary representation of an integer as not exist

(Name) Alternatively, for selecting a specified key

 

a = "%(name)s-----%(age)d "%{'name':'xx','age':20}
print(a)

 

Results of the:

xx-----20

flags optional, alternative values ​​are:

• + Right aligned; added just before the positive, negative numbers preceded by a minus sign;
• - Left; unsigned positive front, a minus sign before the negative;
• Right-aligned spaces; spaces, a minus sign before the negative before positive number;
• Align Right 0; unsigned before positive and negative numbers preceded by a minus sign; the space filled with 0

width optional, possession of width

account name 10, +, right justified, age accounted for 10, -, Left

b = "%(name)+10s————————%(age)-10d————————"%{'name':'xx','age':20}
print(b)

Results of the:

        xx————————20        ————————

 Space, right-aligned

 0, the space is filled with 0

c = "------%(year) d******%(age)010d "%{'year':2016,'age':-20}
print(c)

Results of the:

------ 2016******-000000020 

.precision optional decimal places reserved

Only two decimal places

d = '--------%(p).2f'%{'p':1.23456}
d1 = '--------%(p)f'%{'p':1.23456}
print(d)
print(d1)

Results of the:

--------1.23
--------1.234560

typecode Required

• C, integers: a number into its corresponding unicode values, decimal range 0 <= i <= 1114111 (py27 only supports 0-255); character: adding a character to the specified position
• O, the octal notation is converted into an integer, and formats it into the designated location
• x, an integer converted into hexadecimal notation, and formats it into the designated location

e = 'c *** ***%%% *** the x'% (65,15,15)
print (e)

Results of the:

***A***17***f

• E, integer, floating-point numbers into scientific notation, and formats it into the designated location (lowercase e)
• E, converting the integer, floating-point number in scientific notation, and formats it to the specified position (uppercase E)

f = '-----% (num) ------% of (whether) E'% { 'or' 1000000000}
print(f)

Results of the:

-----1.000000e+09------1.000000E+09

• g, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)
• G, automatic adjustment convert integer, float to float or scientific notation (more figures in scientific notation), and formats it to a specified location (if it is a scientific notation E;)

g '-----% (num) g ------% (num1) G'% { 'whether', 1000000000, 'num1': 100}
print(g)

Results of the:

-----1e+09------100

• %, When the format string flag is present, it is necessary %% represented by a percent sign (similar to turn back effect)

s = 'aaa %'
print(s)
s1 = 'aaa %s %%'%('bbb')
print(s1)

Results of the:

aaa %
aaa bbb% 

format mode

Defined digital format to: Start Number '. I met ':' characters know you want to define a number of display formats. Defined as sequential format 

[[fill]align][sign][#][0][width][,][.precision][type]

• [Optional] fill the space filled with character
• [optional] align alignment (in conjunction with the use of width)
• <, Left-aligned content
• > Contents in the right alignment (default)
• = Contents in the right alignment, the symbol on the left pad characters, and only valid digital type. Even: digital sign + filler +
• ^, Centered content
• sign [optional] whether the symbol numbers
  • +, Positive plus plus plus minus minus sign;
  •  - a positive sign change, plus minus negative sign;
  • Plus negative space, plus space, negative sign;
• # [Optional] For binary, octal, hexadecimal, if coupled with # displayed 0b / 0o / 0x, or do not show
• , [Optional] is added to a digital separators, such as: 1,000,000
• [optional] format bit width occupied by the width
• .precision [optional] decimal place precision reserved
• type [optional] format type
  • Incoming "string type" parameter
    • s, string type data format
    • Blank, unspecified type, the default is None, with s
  • Incoming "integer type" parameter
    
    • b, will be automatically converted to decimal integer of 2 hexadecimal format then
    • c, will automatically convert a decimal integer to its corresponding unicode character
    • d, decimal integer
    • o, it will be automatically converted to decimal integer octal and format;
    • x, the decimal integer automatically converted into a hexadecimal format and (lower case x)
    • X, will be automatically converted to decimal integer in hexadecimal format and then (upper case X)
  • Passed "or decimal floating-point type" parameter
    • E, is converted to scientific notation (lowercase e) shows, then format;
    • E, is converted to scientific notation (uppercase E), and format;
    • F, is converted to floating point (the default after the decimal point 6) shows, then format;
    • F., Is converted to floating point (the default after the decimal point 6) shows, then format;
    • g, e and f are automatically switched
    • G, automatically switches E and F
    • %, Shows the percentage (default display 6 decimal place)

 

[Optional] fill the space filled with character

[optional] align alignment (in conjunction with the use of width)

• <, Left-aligned content
• > Contents in the right alignment (default)
• = Contents in the right alignment, the symbol on the left pad characters, and only valid digital type. Even: digital sign + filler +
• ^, Centered content

[optional] format bit width occupied by the width

s1 ='---{:*^20s}----'.format('welcome')
print(s1)
s2 ='---{:*>20s}----'.format('welcome')
print(s2)
s3 ='---{:*<20s}----'.format('welcome')
print(s3)

Results of the:

---******welcome*******----
---*************welcome----
---welcome*************----

# [Optional] For binary, octal, hexadecimal, if coupled with # displayed 0b / 0o / 0x, or do not show

• b, will be automatically converted to decimal integer of 2 hexadecimal format then
• c, will automatically convert a decimal integer to its corresponding unicode character
• d, decimal integer
• o, it will be automatically converted to decimal integer octal and format;
• x, the decimal integer automatically converted into a hexadecimal format and (lower case x)
• X, will be automatically converted to decimal integer in hexadecimal format and then (upper case X)

Three methods of representation

a1 = "numbers: {:b},{:o},{:d},{:x},{:X}, {:%},{:c}".format(15, 15, 15, 15, 15, 15.87623,65)
a2 = "numbers: {0:b},{0:o},{0:d},{0:x},{0:X}, {0:%},{1:c}".format(15,65)
A3 = "numbers: {Surely, b}, {whether: o}, {Surely, d}, {whether x}, {Surely, 10}, {num%}, {c, c}". format ( Surely = 15, C = 65)
print(a1)
print(a2)
print(a3)

Results of the:

numbers: 1111,17,15,f,F, 1587.623000%,A
numbers: 1111,17,15,f,F, 1500.000000%,A
numbers: 1111,17,15,f,F, 1500.000000%,A

, [Optional] is added to a digital separators, such as: 1,000,000

.precision [optional] decimal place precision reserved

n = '{---} ---- :, d. size (10000000)
n1 = '--- {:. 2f} ----'. format (1.2345)
print(n)
print(n1)

Results of the:

---10,000,000----
---1.23----

 format commonly used format

tp1 = "i am {}, age {}, {}".format("seven", 18, 'alex')
tp2 = "i am {}, age {}, {}".format(*["seven", 18, 'alex'])
tp3 = "i am {0}, age {1}, really {0}".format("seven", 18)
tp4 = "i am {0}, age {1}, really {0}".format(*["seven", 18])
tp5 = "i am {name}, age {age}, really {name}".format(name="seven", age=18)
tp6 = "i am {name}, age {age}, really {name}".format(**{"name": "seven", "age": 18})
tp7 = "i am {0[0]}, age {0[1]}, really {0[2]}".format([1, 2, 3], [11, 22, 33])
tp8 = "i am {:s}, age {:d}, money {:f}".format("seven", 18, 88888.1)
tp9 = "i am {:s}, age {:d}".format(*["seven", 18])
tp10 = "i am {name:s}, age {age:d}".format(name="seven", age=18)
tp11 = "i am {name:s}, age {age:d}".format(**{"name": "seven", "age": 18})
print(tp1)
print(tp2)
print(tp3)
print(tp4)
print(tp5)
print(tp6)
print(tp7)
print(tp8)
print(tp9)
print(tp10)
print(tp11)

Results of the:

i am seven, age 18, alex
i am seven, age 18, alex
i am seven, age 18, really seven
i am seven, age 18, really seven
i am seven, age 18, really seven
i am seven, age 18, really seven
i am 1, age 2, really 3
i am seven, age 18, money 88888.100000
i am seven, age 18
i am seven, age 18
i am seven, age 18