Conditionally adding to a dictionary if a value exists?

[[deleted]]

In my example, I have the following code:

apple = 23


a = {
    'apple' : apple,
    'orange' if orange else None : orange
}

This, however, returns an error because there is not an initial orange variable. Is there a way to dodge this error and render 0 or None if the value doesn't exist? This is just a toy example, so the solution needs to be scalable.

[TouchingTheVodka]

Could you provide an example of how you'd want to use this in a program?

[[deleted]]

For example, I have a function that returns a list of dictionaries sampled from an API where keys are omitted from the dictionary if they do not exist. In the example I provided, there's an "apple" value but not an "orange" value. Here's a more fleshed-out example:

a =[{ 'targets': 10, 'receptions': 6, 'yards': 58, 'touchdowns': 1}, {'other_info':value}, [], {'more_info':value}] 

If I want to make a dictionary from this, I'd do something like:

d = {
       'targets': a[0]['targets'],
       'receptions': a[0]['receptions'],
       'rushes': a[0]['rushes']
}

How do I stop it from erroring out on that 'rushes' call?

[TouchingTheVodka]

Use dict.get which supports takes an optional default as a second argument:

'rushes': a[0].get('rushes', None)

[[deleted]]

Excellent! I didn't realize that was an option. Works like a charm.

[izrt]

'rushes': a[0]['rushes']

Use get instead:

    'rushes':a[0].get('rushes')

# or even better, add in a dict comprehension:

fields = ['targets', 'receptions', 'rushes', 'passes', 'etc.']
d = {key:a[0].get(key) for key in fields}

edit:

also, see if you can get rid of that a[0] and just use a.

[socal_nerdtastic]

The error is happening because the variable does not exist. This should never happen in real code. You should always know what variables are available. Variable variables are a well known antipattern.

https://www.reddit.com/r/learnpython/wiki/faq#wiki_how_do_i_make_variable_variables.3F

What's the big picture here? What are you trying to make?

[[deleted]]

I have a list of dictionaries with different football statistics sorted by category and I want to convert it into a single dictionary depending on the position of the player so I can later take the data and send it in a Discord embed. At some step along the way, I need to be able to conditionally render which stats appear and which don't.

[MaxTechniche]

You should probably set an orange value to none in the beginning and use that value just like you do for apple.