Python function with if-else statement outputting incorrectly

Question

why is my function outputting incorrectly? I am thinking something is working wrong with the if-else statements but idk.

def standardize_gender(gen):
    gen = gen.strip()
    gen = gen.lower()

    if 'female' or 'f' or 'woman' or 'famale' or 'women' in gen:
        put = 'female'
    elif 'male' or 'man' or 'm' or 'men' in gen:
        put = 'male'
    elif 'nonbinary' or 'transgender' in gen:
        put = 'nonbinary_or_trans'
    else:
        put = np.nan
    return put

standardize_gender('male') #Outputs 'female'

Does this answer your question? [Check if multiple strings exist in another string](https://stackoverflow.com/questions/3389574/check-if-multiple-strings-exist-in-another-string) — wjandrea, May 17 '20 at 23:56

score 2 · Answer 1 · edited May 18 '20 at 00:04

This is because your expression actually looks something like this

('female') or ('f') or ('woman') or ('famale') or ('women' in gen)

Since 'female' is not an empty string, the first if block is entered.

What you probably want is something like this:

if any(x in gen for x in ['female', 'f', 'woman', 'famale', 'women']):
  put = 'female'

The any function takes an iterable and returns True if any one of them is truthy. The comprehension (everything inside the parentheses) provides that by going through every element in the list ['female', 'f', 'woman', 'famale', 'women'] and checking if that element (x) is present in gen.

score 0 · Answer 2 · edited May 18 '20 at 00:49

0

Your or statement is wrong - you have to do something like if 'female' in gen or if 'woman' in gen..., (each individually). Yours is basically saying if 'female' , which would be considered True.

edited May 18 '20 at 00:49

mrghofrani

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answered May 17 '20 at 23:53

formicaman

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Don't do them individually, use `any` like the other answers recommend – wjandrea May 18 '20 at 00:02

score 0 · Answer 3 · edited May 18 '20 at 00:00

When you use or in your if statement, it checks if the left of the or is truthy. When you write if 'female': in python, a non-empty string is truthy so the program continues into the if block. This is why you are getting "female" all the time. To avoid this, you can use:

female_conditions = ['female', 'f', 'woman', 'famale', 'women']
if any(cond in gen for cond in female_conditions):
    # do something here

Python function with if-else statement outputting incorrectly

3 Answers3