@@ -88,7 +88,62 @@ while(i < 10):
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print (" {} is less than 10" .format(i))
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i += 1
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```
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- ` .format() ` is a type of printing.
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+
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+ ### String formatting
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+ There are a few ways to format a string in Python.
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+
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+ + Using the ` % ` operator
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+ Strings can be formatted using the % operator:
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+
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+ ``` python
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+ >> > foo = ' world'
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+ >> > ' Hello %s ' % foo
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+ ' Hello world'
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+ ```
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+
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+ To subsitute multiple instances, wrap the right hand side in a Tuple:
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+
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+ ``` python
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+ >> > foo = ' James'
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+ >> > bar = ' Nancy'
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+ >> > ' Hi, my name is %s and this is %s ' % (foo, bar)
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+ ' Hi, my name is James and this is Nancy'
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+ ```
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+
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+ You can also do variable subsitutions with a dictionary:
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+
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+ ```
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+ >>> dict = { "name": "Mike", "country": "Canada" }
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+ >>> 'I am %(name)s and I am from %(country)s' % dict
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+ 'I am Mike and I am from Canada'
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+ ```
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+
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+ + ` .format() `
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+
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+ Introduced in Python 3, but is available in Python 2.7+
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+
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+ ``` python
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+ >> > ' Hello {} ' .format(' world' )
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+ ' Hello world'
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+ ```
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+
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+ Similar to the above, subsitutions can be referred by name:
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+
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+ ``` python
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+ >> > ' Hi {name} , your total is ${total} ' .format(name = ' Bob' , total = 5.50 )
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+ ' Hi Bob, your total is 5ドル.5'
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+ ```
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+
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+ + f-Strings
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+ Available in Python 3.6+. Works similar to the above, but is more powerful as arbitrary Python expressions can be embedded:
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+ ``` python
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+ >> > a = 5
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+ >> > b = 10
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+ >> > f ' Five plus ten is { a + b} and not { 2 * (a + b)} . '
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+ ' Five plus ten is 15 and not 30.'
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+ ```
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## Data Structures
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