Core Python / String Formatting

Review Questions

1. What is the syntax for using new-style string formatting in Python?

   To format a string, call the format() function on that string. "{:d}".format(10)

   The formatting codes have this specification: {[name]:[fill][alignment][sign][minwidth][group][.][maxchars]type}

   You are not expected to memorize the specification or the various codes, but with a reference card, you should be comfortable formatting strings.

2. What is the difference between using positional arguments and keyword arguments in string formatting?

   Immediately after the left curly brace {, an optional positional or name argument may be specified. We can then use that position or name to map to variables (expressions) specified in the arguments to format().

3. How do you insert a value into a string using the format() method?

   To insert a value into a string using the format() method, you use replacement fields within the string, denoted by curly braces {}. The values to be inserted are provided as arguments to the format() method.

   name = "Alice"
   age = 25
   
   formatted_string = "My name is {} and I'm {} years old.".format(name, age)
   print(formatted_string)
   

Drill Steps

year = 2024
print("{:d} is the current year".format(year))
print("{:x^8d}".format(year))
print("{:x}".format(year))
print("{:0>7d}".format(year))
pi = 3.14159
print("{:.4f} is an approxiamate value of pi".format(pi))
print("{:x^10.2f}".format(pi))
print("{:0>10.5f}".format(pi))
print("{:12.8f}".format(pi))