{"library":"numexpr","title":"Fast numerical expression evaluator for NumPy","description":"NumExpr is a Python library that provides a fast numerical expression evaluator for NumPy. It accelerates array operations by avoiding memory allocation for intermediate results, leading to better cache utilization and reduced memory access. It also leverages multi-threading to utilize multiple CPU cores and supports Intel's Math Kernel Library (MKL) for further performance gains, especially with transcendental functions. The current version is 2.14.1, and it maintains a regular release cadence.","language":"python","status":"active","last_verified":"Wed May 13","install":{"commands":["pip install numexpr"],"cli":null},"imports":["import numexpr as ne","ne.evaluate('expression')"],"auth":{"required":false,"env_vars":[]},"quickstart":{"code":"import numpy as np\nimport numexpr as ne\n\n# Create large arrays for demonstrating performance benefits\na = np.arange(1_000_000, dtype=np.float64)\nb = np.arange(1_000_000, 0, -1, dtype=np.float64)\n\n# Evaluate a complex expression using numexpr\nresult_ne = ne.evaluate(\"sin(a) + arcsinh(a/b) + (a * b - 4.1 * a) > 2.5 * b\")\n\nprint(result_ne)\nprint(f\"Result type: {result_ne.dtype}\")\n\n# You can also set the number of threads dynamically\n# print(f\"Current numexpr threads: {ne.nthreads}\")\n# ne.set_num_threads(4)\n# print(f\"New numexpr threads: {ne.nthreads}\")","lang":"python","description":"This quickstart demonstrates how to import `numexpr` and use its primary `evaluate` function. It takes a string expression, which is then parsed and efficiently computed on large NumPy arrays, leveraging NumExpr's optimizations and multi-threading. 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