CODEWITHSUNDEEP
pythonpython-3.x
ChocolateOverflow
ChocolateOverflow

Reputation: 480

Making a dictionary of functions

I'm trying to make a dictionary of lambda functions. It should be able to take a key and process whichever function is bound to that key and output the result.

func_dict = {
    "func1" : (z = lambda x, y: x + y),
    "func2" : (z = lambda x, y: x * y)
} # include benchmark functions

func = input("Choose a function: ")
output = func_dict[func](3, 5)
print(output)

That sample should print 8 but it doesn't run and simple gives me can't assign to dictionary display error on

    {
    "func1" : (z = lambda x, y: x + y),
    "func2" : (z = lambda x, y: x * y)
}

(indentation doesn't seem to be the problem) I'd like to avoid using eval() & exec() if possible.

Upvotes: 4

Views: 436

Answers (3)

surya bista
surya bista

Reputation: 33

Your dictionary is fine dude.

func_dict = {
    "func1" : lambda x, y: x + y,
    "func2" : lambda x, y: x * y
} # include benchmark functions

func = input("Choose a function: ")
output = func_dict[func](3, 5)
print(output)

Upvotes: 1

Paymahn Moghadasian
Paymahn Moghadasian

Reputation: 10329

I think your assignment of z = is what's broken.

Try

func_dict = {
    "func1" : lambda x, y: x + y,
    "func2" : lambda x, y: x * y
} # include benchmark functions

Here's it working for me:

 ❯❯❯ python
Python 3.6.7 (default, Dec  3 2018, 11:24:55)
[GCC 4.2.1 Compatible Apple LLVM 10.0.0 (clang-1000.10.44.4)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> func_dict = {
    "func1" : lambda x, y: x + y,
    "func2" : lambda x, y: x * y
} # include benchmark functions... ... ...
>>> func_dict["func1"](1,2)
3

Upvotes: 5

Devesh Kumar Singh
Devesh Kumar Singh

Reputation: 20490

Your initial attempt is going to raise a syntax error.

Instead you would want to assign the definition of your lambda function directly to the key as follows

#The lambda function is assigned as a value of the keys
func_dict = {
    "func1" : lambda x, y: x + y,
    "func2" : lambda x, y: x * y
} 

func = input("Choose a function: ")
output = func_dict[func](3, 5)
print(output)

The output will be

Choose a function: func1
8

Choose a function: func2
15

Upvotes: 10

Related Questions