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Aswin Barath
Aswin Barath

Posted on • Originally published at dev.to

Lambda expressions in python

Lambda expressions in python are one-time anonymous functions which we don't need more than once.

Consider the following example where we use a function to multiply a list of numbers with the mathematical constant pi:

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Output:

[3.14, 6.28, 9.42]
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What if I say that we could do all of this in one line.
Well, it turns out we can do it.
We can convert the above example into a single line of code using Lambda expressions.

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Output:

[3.14, 6.28, 9.42]
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Lambda function

Syntax: lambda arguments : expression

  • A lambda function can take any number of arguments, but can only have one expression:

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Output:

94
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Why do we need to use Lambda functions?

  • Well, it contributes to the code by reducing the number of lines of functions which we may use only once.
  • To take it to the next level, we can return an anonymous function inside another example:

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Output:

62.800000000000004
119.32000000000001
31.400000000000002
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As you can see, we got to use the same function to calculate different values.
You get to create a function definition that takes one argument, and that argument will be multiplied with an unknown number (which you can specify in the future).

That's the power of lambda expressions.

Code along and learn more...

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