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Efficiency of repeatedly appending to a List

• To: mathgroup at smc.vnet.net
• Subject: [mg71091] Efficiency of repeatedly appending to a List
• From: "Andrew Moylan" <andrew.j.moylan at gmail.com>
• Date: Wed, 8 Nov 2006 06:07:11 -0500 (EST)

Hi all,

Recently I asked about efficient ways to insert items into a sorted
List such that the new list was also sorted [1]. I received suggestions
to linearly search through the list and find the right place to insert
the new time (search time = O(N), where N is the size of the list), and
also suggestions to use a faster binary search to locate the right
place to insert the new time (search time = O(Log[N])).

This caused me to wonder about the efficiency of appending items to
Lists in Mathematica in general. Is it an O(N) operation (i.e.,
something akin to a realloc in C)? Or does Mathematica employ some sort
of anticipatory memory allocation scheme to make adding new elements to
lists usually faster than O(N)?

Cheers,
Andrew

[1]
http://groups-beta.google.com/group/comp.soft-sys.math.mathematica/browse_thread/thread/0c329c83dec5a1b1

• Follow-Ups:
  • Re: Efficiency of repeatedly appending to a List
    • From: János <janos.lobb@yale.edu>