{"id":5816,"date":"2022-07-07T00:03:52","date_gmt":"2022-07-07T00:03:52","guid":{"rendered":"https:\/\/pariswells.com\/blog\/?p=5816"},"modified":"2022-07-07T00:03:52","modified_gmt":"2022-07-07T00:03:52","slug":"speeding-up-addition-in-arrays-in-powershell","status":"publish","type":"post","link":"https:\/\/pariswells.com\/blog\/research\/speeding-up-addition-in-arrays-in-powershell","title":{"rendered":"Speeding up Addition in Arrays in Powershell"},"content":{"rendered":"

Note that the use of the += addition operator on an array in powershell can run \/very\/ slowly if you\u2019re working with a large array. This is because under the hood an array is allocated a fixed chunk of memory and modifying the array requires creating a newly sized fixed chunk of memory and copying all of the data into the new memory.<\/p>

https:\/\/docs.microsoft.com\/en-us\/powershell\/scripting\/dev-cross-plat\/performance\/script-authoring-considerations?view=powershell-7.2#array-addition<\/a><\/p>

There are two ways of working around this. Either by using a c# type System.Collection.ArrayList or by using a neat powershell trick (below). If you\u2019re only working on small arrays the overhead of this is going to be negligible and may not warrant rewriting to an arraylist.<\/p>

\u00a0<\/p>

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Note that the use of the += addition operator on an array in powershell can run \/very\/ slowly if you\u2019re working with a large array. This is […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-5816","post","type-post","status-publish","format-standard","hentry","category-research"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t