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26 lines
777 B
26 lines
777 B
10 years ago
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---
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layout: post
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status: publish
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published: true
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title: 'Python: Performance Benchmark'
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author:
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display_name: 'sipp11'
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date: '2013-11-20'
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categories:
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- coding
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tags: python benchmark
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---
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`[item for sublist in l for item in sublist] is faster than the shortcuts posted so far.
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For evidence, as always, you can use the timeit module in the standard library:
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$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
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10000 loops, best of 3: 143 usec per loop
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$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l, [])'
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1000 loops, best of 3: 969 usec per loop
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$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'reduce(lambda x, y: x+y,l)'
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1000 loops, best of 3: 1.1 msec per loop
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