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pythonlist-comprehension

List comprehension to remove element from python list if it is only digits (even if there are "_" or "-" in it)

I have many lists like this

synonyms = ["3,2'-DIHYDROXYCHALCONE", '36574-83-1', '36574831', "2',3-Dihydroxychalcone",  '(E)-1-(2-hydroxyphenyl)-3-(3-hydroxyphenyl)prop-2-en-1-one', MLS002693861]

from which I need to remove all elements that are comprised of only digits. I can't figure out how to remove element [1] because it's only digits but has random intervening dashes.

Of course, this doesn't work since the dashes make the element not a digit:

synonym_subset = [x for x in synonym_subset if not (x.isdigit())]

And I can't just remove the dashes because I want the dashes in the other elements to be retained:

synonym_subset = [x.replace('-','') for x in synonym_subset]

I could run the above to find the index of the elements to be removed, then remove them that way, but I was hoping for a one-liner.

Thanks.

Solution

  • Try:

    synonyms = [
    "3,2'-DIHYDROXYCHALCONE",
    "36574-83-1",
    "36574831",
    "2',3-Dihydroxychalcone",
    "(E)-1-(2-hydroxyphenyl)-3-(3-hydroxyphenyl)prop-2-en-1-one",
    "MLS002693861",
]

out = [s for s in synonyms if not all(ch in "0123456789-_" for ch in s)]
print(out)

    Prints:

    [
    "3,2'-DIHYDROXYCHALCONE",
    "2',3-Dihydroxychalcone",
    "(E)-1-(2-hydroxyphenyl)-3-(3-hydroxyphenyl)prop-2-en-1-one",
    "MLS002693861",
]