python - How do I split on the space-separated math operators here? -

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i have user calculator accepts both numbers , user-defined variables. plan split statement on space-delimited operator, e.g. ' + ':

import re query = 'house-width + 3 - y ^ (5 * house length)' query = re.findall('[+-/*//]|\d+|\d+', query) print query  # ['house-width + ', '3', ' - y ^ (', '5', ' * house length)']  expecting: ['house-width', '+', '3', '-', 'y', '^', '(5', '*', 'house length)']

using re.split capturing parentheses around split pattern seems work effectively. long have capturing parens in pattern patterns splitting on kept in resulting list:

re.split(' ([+-/*^]|//) ', query) out[6]: ['house-width', '+', '3', '-', 'y', '^', '(5', '*', 'house length)']

(ps: i'm assuming original regex want catch // integer division operators, can't single character class, i've moved outside character class special case.)


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