{"kind":"task","effective_mode":"full","benchmark":{"kind":"benchmark","effective_mode":"full","slug":"ds-1000","formal_name":"DS-1000","introduction":"DS-1000 builds 1,000 data-science problems from real StackOverflow questions across seven libraries including NumPy, Pandas and Matplotlib. The problems are perturbed so that recalling the original answer does not solve them.","introduction_ja":"","introduction_en":"","category":"Category not supplied","task_count":null,"acquisition_status":"Acquisition status not supplied","official_url":"https://ds1000-code-gen.github.io/","indexing_mode":"index","profile":{"resources":[],"task_format":"","scoring":"","metric":"","size":"","answer_access":"","license":"","citation":"","maintainer":"","released":"","why_hard":"","related":[],"history":"","construction":"","limitations":"","saturation":"","scores":[]}},"task_id":"332abdd1-b7e7-5e8d-a09f-0d79673302f9","task_key":"default--test--407","task_revision_id":"1","upstream_id":"407","short_description":"I'm looking for a fast solution to MATLAB's accumarray in numpy. The accumarray…","config":"default","split":"test","body":"{\"library\":\"Numpy\",\"prompt\":\"Problem:\\nI'm looking for a fast solution to MATLAB's accumarray in numpy. The accumarray accumulates the elements of an array which belong to the same index.\\nNote that there might be negative indices in accmap, and we treat them like list indices in Python.\\n An example:\\na = np.arange(1,11)\\n# array([ 1,  2,  3,  4,  5,  6,  7,  8,  9, 10])\\naccmap = np.array([0,1,0,0,0,-1,-1,2,2,1])\\nResult should be\\narray([13, 12, 30])\\nIs there a built-in numpy function that can do accumulation like this? Using for-loop is not what I want. Or any other recommendations?\\nA:\\n<code>\\nimport numpy as np\\na = np.arange(1,11)\\naccmap = np.array([0,1,0,0,0,-1,-1,2,2,1])\\n</code>\\nresult = ... # put solution in this variable\\nBEGIN SOLUTION\\n<code>\\n\"}","display_format":"code","language":"","answer_status":"published","assets":[],"source_url":"https://ds1000-code-gen.github.io/","history":"initial import","indexing_mode":"index","subproblems":[],"grids":[]}