34 lines
885 B
Python
34 lines
885 B
Python
"""
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Handy financial calculations.
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"""
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import math
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import itertools
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def humanize(number, digits=1):
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"""Convert large numbers to something with at most 3 digits and
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a letter suffix (eg. k: thousand, M: million, B: billion).
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"""
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try:
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float(number)
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except ValueError:
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return 0
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if not number or number <= 0:
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return number
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mag2suffix = {3: 'k', 6: 'M', 9: 'B'}
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mag = math.floor(math.log(number, 10))
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if mag < 3:
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return number
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maxmag = max(itertools.takewhile(lambda key: mag >= key, mag2suffix))
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return "{:.{digits}f}{}".format(
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number/10**maxmag, mag2suffix[maxmag], digits=digits)
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def percent_change(init, new):
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"""Calcuate the percentage change of some ``new`` value
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from some initial value, ``init``.
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"""
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if not (init and new):
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return 0
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return (new - init) / init * 100.
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