67 lines
1.9 KiB
Python
67 lines
1.9 KiB
Python
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class EngineeringNumberConverter():
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prefixes = [
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('y', 1e-24),
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('z', 1e-21),
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('a', 1e-18),
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('f', 1e-15),
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('p', 1e-12),
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('n', 1e-9),
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('u', 1e-6),
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('m', 1e-3),
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# We skip centi and dezi because no one really uses these besides for length measurements
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('', 1),
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# We also skip h for hekto
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('k', 1e3),
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('M', 1e6),
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('G', 1e9),
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('T', 1e12),
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('P', 1e15),
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('E', 1e18),
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('Z', 1e21),
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('Y', 1e24),
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]
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it_prefixes = [
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('', 1),
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('Ki', 1024),
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('Mi', 1024*1024),
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('Gi', 1024*1024*1024),
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('Ti', 1024*1024*1024*1024)
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]
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@classmethod
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def number_to_engineering(c, number, it_unit = False):
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"""
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Convert a number to engineering SI syntax with prefix.
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This function will return a tuple of (new_number, prefix)
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"""
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if it_unit:
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used_prefixes = c.it_prefixes
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else:
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used_prefixes = c.prefixes
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if (len(used_prefixes) < 2):
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return (number / used_prefixes[0][1], used_prefixes[0])
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for i, (prefix, scale) in enumerate(used_prefixes[1:], 1):
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if number < scale:
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return (number / used_prefixes[i-1][1], used_prefixes[i-1][0])
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return (number / used_prefixes[-1][1], used_prefixes[-1][0])
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@classmethod
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def engineering_to_number(c, input):
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cleaned_input = input.strip().replace(' ', '')
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selected_scaling = 1
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for (prefix, scale) in c.prefixes+c.it_prefixes:
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if prefix == '':
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continue
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if cleaned_input.endswith(prefix):
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cleaned_input = cleaned_input.replace(prefix, '')
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selected_scaling = scale
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break
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return float(cleaned_input) * selected_scaling |