Aug 19, 2008 · Lambda calculus codifies the correct way to do these substitutions. Given that y = x−1 is a valid rearrangement of the second equation, this: λ y = x−1 means a function substituting the …

Here is another really good reference which explains very well what are lambda expressions in C++: Microsoft.com: Lambda expressions in C++. I especially like how well it explains the parts of a …

I saw some examples using built-in functions like sorted, sum etc. that use key=lambda. What does lambda mean here? How does it work? For the general computer science concept of a lambda, see …

Lambda functions are most useful in things like callback functions, or places in which you need a throwaway function. JAB's example is perfect - It would be better accompanied by the keyword …

Mar 8, 2011 · The lambda construct is a shorter way to define a simple function that calculates a single expression. The def statement can be inconvenient and make the code longer, broken up and harder …

An easy way to perform an if in lambda is by using list comprehension. You can't raise an exception in lambda, but this is a way in Python 3.x to do something close to your example:

The closure of a lambda expression is this particular set of symbols defined in the outer context (environment) that give values to the free symbols in this expression, making them non-free …

Dec 18, 2008 · Lambda is a means of creating an anonymous function or closure. In imperative languages (and functional ones) it is equivalent to allowing nested functions where the inner function …

I don't quite understand the syntax behind the sorted() argument: key=lambda variable: variable[0] Isn't lambda arbitrary? Why is variable stated twice in what looks like a dict?

May 31, 2013 · 1 (lambda x: x%2) is a function, and dividing a function by 2 doesn't make any sense. You probably want to call it and divide what the value it returned.