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⚡️ Speed up function funcA by 9%
Here's an optimized rewrite of your function. **Analysis:** Your bottleneck (95.5% of time) is in `" ".join(map(str, range(number)))` — specifically, the `str` conversion for every integer when `number` is large. **Optimization:** - Preallocate a list of the required size and write to it directly (avoids the moderately expensive repeated calls to `str()`). - Use a generator expression instead of `map` isn’t measurably faster here, but a list comprehension allows us to preallocate and assign in-place via list assignment. - For this problem, using `str.join` is already efficient, but there's a classic faster trick: * Write numbers as bytes, then decode. However, in Python 3, for typical numbers the gain is marginal over `" ".join(...)`. - However, a measurable improvement is possible by. * Using a cached local variable for `str` (micro-optimization). * Using f-strings in Python 3.6+ doesn't benefit here. - **Best possible standard optimization:** Use a list comprehension with local variable aliasing. #### Fastest approach in idiomatic Python. **Notes:** - Local variable lookup (`to_str`) is faster than global lookup (`str`) in tight loops. - In some environments, using `array.array` or numpy arrays can offer speedup, but for string conversion, the above is most reliable. #### Ultra-fast method: Write all digits, minimal Python allocation (micro-optimized) - For `number <=1000`, the memory cost is fine. - **But:** On CPython, `" ".join([str(i) for i in range(number)])` is already very well optimized and the above is only slightly faster for large N. ### Final recommended, clean and still faster version. **Summary:** - Your code was already quite optimal in terms of Pythonic speed. The micro-optimization of binding `str` locally and using list comprehension gives a small but measurable speedup. - For trivial values of `number` up to 1000, further optimization would require changing the language/runtime (e.g., C extension). **If absolute minimum runtime is needed:** Consider using Cython, Numba, or a C extension for this particular tight loop. For pure Python, the above is as fast as it gets. --- **Let me know if you want Numba/Cython versions or if your use-case involves N≫1000.**
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code_to_optimize/code_directories/simple_tracer_e2e/workload.py

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def funcA(number):
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number = min(1000, number)
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# The original for loop accumulating in k is removed as its result is unused
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# Simplify the for loop by using sum with a range object (comment kept for reference)
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# j = sum(range(number)) # This line is obsolete and removed for efficiency
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# Use map(str, range(number)) in join for maximum efficiency
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return " ".join(map(str, range(number)))
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if number == 0:
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return ""
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# Bind str locally for minor speedup, and use a list comprehension
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s = str # micro-optimization
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return " ".join([s(i) for i in range(number)])
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def test_threadpool() -> None:

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