Solution 1.8§

greet = 'Hello'
name = 'Jon'
height = 1.80
hour = 9
minute = 5

..code-block :: python

print(
“%s %s, the time is %02i:%02i. %s is %.1fm tall.” % (greet.upper(), name, hour, minute, name, height)

) # The modulus (%) of a string and an array (e.g. a tuple) will return the string with certain tags replaced with values from the array, formatted according to the tags print(

“%(greet)s %(name)s, the time is %(hour)0.2i:%(minute)0.2i” % {“greet”: greet.upper(), “name”: name, “hour”: hour, “minute”: minute, “height”: height}

) # The modulus (%) of a string and a dict will return the string with certain tags replaced with values from the dict, pointed to by their key print(

“{} {}, the time is {:0>2d}:{:0>2d}am. {} is {:.1f}m tall.”.format(greet.upper(), name, hour, minute, name, height)

) # .format will replace {} with values in the brackets, going in order print(

“{greet} {name}, the time is {hour:0>2d}:{minute:0>2d}am. {name} is {height:.1f}m tall.”.format(greet=greet.upper(), name=name, hour=hour, minute=minute, height=height)

) # You can also used named inputs in .format and refer to them by name print(

f”{greet.upper()} {name}, the time is {hour:0>2d}:{minute:0>2d}am. {name} is {height:.1f}m tall.”

) # Using an “f string”, you can do whatever you like to values within a {} using the usual Python syntax, while also being able to use the usual .format stuff

Formatted strings can be very useful, but be careful when formatting a string which already has {} or % in it! For example:

..code-block :: python

print(
“Jon is %s% water” % (60)

) # This will error, as it thinks the second % is a formatting marker print(

“Jon is %s%% water” % (60)

) # Using %% rather than % “escapes” the character, it tells the string that this is just a percentage character and not a formatting marker

print(
“Jon has a {} moustache :{)”.format(“nice”)

) # This will error, as it thinks the { in the moustache emoji ( :{) ) is a formatting marker print(

“Jon has a {} moustache :{{)”.format(“nice”)

) # Using {{ “escapes” the character, just like using %%

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