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dpb
Posts:
9,242
Registered:
6/7/07


Re: Finding position in array
Posted:
Jun 6, 2014 2:50 PM


On 6/6/2014 1:11 PM, Bruno Luong wrote: > dpb <none@non.net> wrote in message <lmsth7$ekd$1@speranza.aioe.org>... >> On 6/6/2014 12:03 PM, Bruno Luong wrote: >> >> >> >> Yet another approach somewhat akin to Bruno's... >> >> >> >> >> interp1(a,1:length(a),x,'nearest') >> >> ans = >> >> 3 >> > >> > Not completely equivalent, INTERP1 will has the resulting index >> jumps by >> > 1 unit when passing the middle point of the EDGES, whereas HISTC jumps >> > right at the EDGES. >> >> Didn't say it was equivalent; only that it is "_somewhat_ akin to"... > > You should point out the difference, otherwise it can be missleading for > OP.
What's misleading? I pointed out it was an alternative; he didn't specify precisely what solution he wished...you didn't give any explanation of your solution, either or how it differs from FIND.
Seems pretty picky nitting to me...
>> > INTERP1 and HISTC methods can deal with x as vector (not FIND()). >> >> But FIND() returns the specific preceding/following index value >> depending on the usage if that's significant. The vector of lookup >> values is easily dealt with via ARRAYFUN > > IMO ARRAYFUN is a poor choice when speed is important for large array of > x. I often prefer forloop compared to ARRAYFUN.
Whatever...again OP didn't say anything about array size(s) from which to judge whether speed would be an issue or not...




