python f print format code example
Example 1: python f string
"""
An f-string stands for 'function-string' it's just used to work with
strings more appropiately, they do the exact same job as concantenating
strings but are more efficient and readable.
"""
# Concantenating strings:
Age = "25"
print("I am "+Age+" years old.")
# Using f strings:
Age = 25
print(f"I am {Age} years old.")
# ^ notice the letter 'f' at the begining of the string.
# That defines the string as being an f-string.
# A third way of inputting variables into a string is by using
# .format()
Age = "25"
print("I am {} years old.".format(Age))
# If you had more than one variable:
Age = "25"
Name = "Jeff"
print("I am {} years old, and my name is {}.".format(Age,Name))
Example 2: python f-strings
>>> name = "Fred"
>>> f"He said his name is {name!r}."
"He said his name is 'Fred'."
>>> f"He said his name is {repr(name)}." # repr() is equivalent to !r
"He said his name is 'Fred'."
>>> width = 10
>>> precision = 4
>>> value = decimal.Decimal("12.34567")
>>> f"result: {value:{width}.{precision}}" # nested fields
'result: 12.35'
>>> today = datetime(year=2017, month=1, day=27)
>>> f"{today:%B %d, %Y}" # using date format specifier
'January 27, 2017'
>>> f"{today=:%B %d, %Y}" # using date format specifier and debugging
'today=January 27, 2017'
>>> number = 1024
>>> f"{number:#0x}" # using integer format specifier
'0x400'
>>> foo = "bar"
>>> f"{ foo = }" # preserves whitespace
" foo = 'bar'"
>>> line = "The mill's closed"
>>> f"{line = }"
'line = "The mill\'s closed"'
>>> f"{line = :20}"
"line = The mill's closed "
>>> f"{line = !r:20}"
'line = "The mill\'s closed" '
Example 3: format specificer f strings python
#!/usr/bin/env python3
val = 12.3
print(f'{val:.2f}')
print(f'{val:.5f}')