Re: AW: position of matrix elements for intervals
- To: mathgroup at smc.vnet.net
- Subject: [mg78532] Re: AW: position of matrix elements for intervals
- From: dh <dh at metrohm.ch>
- Date: Tue, 3 Jul 2007 05:45:19 -0400 (EDT)
- References: <f6alhs$hld$1@smc.vnet.net>
Hi Kristoph,
that is a bit more involved. We ned the following ideas:
-to get ,the first element "from below", we determine all and take the
last one (index -1)
- to be able to specify the column, we make a conditional pattern for
sublists.
- pay attention to the fact that positions are: {row,column}
with this we have:
Table[Append[Position[data,x:{__}/;x[[i]]>0.99][[-1]],i],{i,1,3}]
hope this helps, Daniel
Kristoph Steikert wrote:
> Thanks a lot, this was helpful! But it seems that I have an extended problem
> and I would kindly ask for your help.
> Do you have an idea how to allocate the position of the first element
> satisfying the condition of each column from below?
>
> Example:
> data = {{1, 1.`, 0.9999999932328848`}, {1.`, 0.9985849617864345`,
> 3.7570598417296495`*^-108}, {0.9999999999267634`,
> 4.0643593704937925`*^-207, 0}};
>
> I'm looking for the position from below of the first element in each column
> meeting #>=0.99.
>
> The output should be:
> {{1,3},{2,2},{3,1}}
>
>
> I appreciate your help very much,
> Kristoph
>
>
>
> -----Urspr=FCngliche Nachricht-----
> Von: hanlonr at cox.net [mailto:hanlonr at cox.net]
> Gesendet: Sonntag, 1. Juli 2007 17:05
> An: kristoph; mathgroup at smc.vnet.net
> Betreff: Re: position of matrix elements for intervals
>
> data = {{1, 1.`, 0.9999999932328848`}, {1.`, 0.9985849617864345`,
> 3.7570598417296495`*^-108}, {0.9999999999267634`,
> 4.0643593704937925`*^-207, 0}};
>
> The second argument to Position must be written as a pattern:
>
> Position[data, _?(# >= 0.99 &)]
>
> {{1, 1}, {1, 2}, {1, 3}, {2, 1},
> {2, 2}, {3, 1}}
>
> Position[data, _?(0.4 <= # <= 0.9999 &)]
>
> {{2, 2}}
>
>
> Bob Hanlon
>
> ---- kristoph <kristophs.post at web.de> wrote:
>> Hi,
>>
>> Assume you have the following table:
>>
>> {{1, 1.`, 0.9999999932328848`}, {1.`, 0.9985849617864345`,
>> 3.7570598417296495`*^-108}, {0.9999999999267634`,
>> 4.0643593704937925`*^-207, 0}}
>>
>> I would like the position of all the elements >= 0.99. Or the position
>> of all the elements of [0.4, 0.9] which in the above table does make a
>> lot of sense.
>> I'm familiar with Position[...,.] but since I look for reals of an
>> interval I would kindly ask for help.
>>
>> Thanks a lot,
>> Kristoph
>>
>>
>
>
>