Python Lambda Expressions Tutorial: what, how, when and why

Take a few minutes to learn about this important feature of the Python language.

[cristinocanga]

These channel still has so much good things to teach
Why does the videos just stopped?

[azulpurpura]

Please don't die, your explanations are good :c

[voytechj]

"if" statement in lambda for fun:
test = lambda x: '>= 0' if x>=0 else '<0'
test(1), test(0), test(-1)


another example => lambda x: 'positive' if x>0 else 'negative' if x<0 else 'zero'

[voytechj]

you mention tkinter, so it is good to know how to make a functions factory with lambdas. In tkinter callbacks cant have arguments and it is hard to distinguish what button was pressed, lambda with catch value can help:

def button_callback(bt_id):
print(f'Button {bt_id}')

for i in range(10):
b = Button(text=f"Button{i}", command=lambda x=i: button_callback(x))
b.pack()

partial from functools can be used as well: b=Button(text=f"Button{i}", command=partial(button_callback, i))

[Murciallog]

Hello Sir! 3 months and not a single new video? :( Are you done with your channel? We miss you man

[Murciallog]

I hope you're doing well, but I'm f... tired waiting of you :) Please come back... There are no quality tutorials on youtube ..

[subhashriroy]

can we use a for loop in a lambda expression?
im getting error

[Sparham]

You coded "def: concatenater()" ... not "def:concatenater(x)"... yet the function knew to pass your provided argument to the lambda expression in the function, could you explain this? Obviously it worked, but shouldn't you need to label your function arguments when defining a function?

[nitishvio]

Hi Live Python I need some help in python