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def doubler(input_number):
return input_number*2
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doubler(45)
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temp_fn = lambda arg : arg*2
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temp_fn(55)
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type(temp_fn)
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It looks silly now, but lambdas work great with map and other productivity functions. You can have other methods and functions that do the heavy lifting and call them in a particular order from a lambda
The map function will perform an operation on all elements of an input list. You can execute a function on all elements of a list without a loop, like a comprehension.
map(function, sequence) --> applies the function for each element in the sequence. The return sequence if of same length as input sequence
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l1 = [1,2,3,4,5,6,7]
#to double elements in this list using list comp
l1_double = [i*2 for i in l1]
l1_double
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#double using map and a function
l1_double_2 = list(map(doubler, l1))
l1_double_2
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#double using map and a lambda function
l1_double_3 = list(map(lambda arg:arg*2, l1))
l1_double_3
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filter function is used to filter out elements in a sequence based on a condition
filter(function, sequence) --> applies the function for each element in sequence, but the return sequence is same or smaller than input based on the condition in the `function`.
The function should return a bool
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#find only the odd numbers --> list comp way
l1_odd = [i for i in l1 if i%2 > 0]
l1_odd
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# find only odd numbers --> filter with lambda way
l1_odd_2 = list(filter(lambda arg:arg%2>0, l1))
l1_odd_2
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