If/else expressions with multiple conditions (1/2)

In the last example, you might notice that we didn't consider the case when revenue is exactly 2000. In that case, we suffer no losses, but at the same time have no profit. Surely there should be a way to modify our code to predict such things.

If you want to check one more condition after you've done another one, use elif. It looks like follows:

if condition1:

do something

elif condition2:

do another

else:

do nothing


              123456
            
if condition1:
    do something
elif condition2:
    do another
else:
    do nothing

A piece of code after the last else will be executed only when all the conditions above don't hold.

For example, remember our last example with string length. Let's modify it a bit and now let's call string large if it has more than 20 symbols, medium - if more than 10 (but surely less than 20), and small otherwise.

# assign some medium string

test = "medium string"

# conditional statements

if len(test) > 20:

print("String: '", test, "' is large")

elif len(test) > 10:

print("String: '", test, "' is medium")

else:

print("String: '", test, "' is small")

# one more checking

test = "small"

# conditional statement

if len(test) > 20:

print("String: '", test, "' is large")

elif len(test) > 10:

print("String: '", test, "' is medium")

else:

print("String: '", test, "' is small")


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# assign some medium string
test = "medium string"

# conditional statements
if len(test) > 20:
    print("String: '", test, "' is large")
elif len(test) > 10:
    print("String: '", test, "' is medium")
else:
    print("String: '", test, "' is small")
    
# one more checking
test = "small"

# conditional statement
if len(test) > 20:
    print("String: '", test, "' is large")
elif len(test) > 10:
    print("String: '", test, "' is medium")
else:
    print("String: '", test, "' is small")

Taak

Swipe to start coding

Modify your code (from exercise about the small store) so if revenue will be exactly 2000 you will receive the message "We are in balance".

Oplossing

# modify your code

revenue = 2000

# modify your conditional statement

if(revenue < 2000):

print("We suffer losses!")

elif(revenue == 2000):

# modify if/else statement with one more condition

print("We are in balance.")

else:

print("Everything is ok!")

Was alles duidelijk?

Bedankt voor je feedback!

Sectie 4. Hoofdstuk 5

# modify your code

revenue = 2000

# modify your conditional statement

if(revenue < 2000):

print("We suffer losses!")

elif(_ _ _):

#modify if/else statement with one more condition

_ _ _

else:

print("Everything is ok!")