In this sample program I'm naming the days 0 through 6 where day 0 is Sunday and day 6 is Saturday. I'm wondering if I can use a lambda expression here for starting day and length of stay and still return the number of the day of the week I would return on. I'm having trouble understanding how to use lambda expressions in a simple example like this.
starting_day = 3
length_of_stay = 10
end_day = (starting_day + length_of_stay) % 7
print("You will come back on day: ", end_day)
Before thinking about how you'd write a lambda function for this, consider how you'd write a normal function. It would probably look something like this:
def day_of_return(starting_day, length_of_stay):
return (starting_day + length_of_stay) % 7
Then you can easily convert this to a lambda function:
day_of_return = lambda starting_day, length_of_stay: (starting_day + length_of_stay) % 7
or, with shorter variable names:
day_of_return = lambda s,l: (s+l) % 7
And then you could call it like this:
print(day_of_return(3,10))
Edit: In the comments, @daragua points out that assigning lambdas to a variable kind of defeats the purpose of a lambda, so you can also remove the assignment altogether:
print((lambda s,l: (s+l) % 7) (3,10)) # This will print 6
anonymous functions :)Lambdas are functions, not expressions. They can be used anywhere a function is used. They are typically anonymous and very short.
print("You will come back on day: ", (starting_day + length_of_stay) % 7), but it would be silly to use a lambdaprint("You will come back on day: ", (lambda start, length: (start + length) % 7)(starting_day, length_of_stay)).