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Re: Removing equal elements from an array [message #49837 is a reply to message #49761]

Wed, 16 August 2006 12:42

Julio[1]
Messages: 52
Registered: May 2005

Member

I'm using only integer values, so the Maarten's code and the Jean's tip
solved my problem. But I agree with you JD, when using float values it
won't work.

Thanks for all the comments!
Julio

JD Smith escreveu:

> On Wed, 16 Aug 2006 10:12:43 -0600, Jean H. wrote:
>
>> Hi,
>>
>> just sort your array based on the 2 fields...
>> you can do something like:
>> maxCol2 = max(a[1,*])
>> sortedIndices = sort([a[0,*]*maxCol2 + a[1,*]])
>> now do as you did before, but using a[0,sortedIndices] and
>> a[1,sortedIndices]
>
>
> This will only work in general for integer valued coordinates, but
> will get you into trouble with floating point. Note the following
> degeneracy, for maxCol2=180.:
>
> .1*180 + 1 == .05 * 180 + 10.
>
> thus, e.g., [.1,1] and [.05,10.] would be considered the same
> coordinates in your method.
>
> The only possibility for arbitrary floats over some range is to cast
> them to integers using a useful precision, and then shifting one set
> of numbers clear of the other.
>
> JD

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[Message index]

		Removing equal elements from an array By: Julio[1] on Tue, 15 August 2006 07:46
		Re: Removing equal elements from an array By: JD Smith on Thu, 17 August 2006 14:21
		Re: Removing equal elements from an array By: news.qwest.net on Thu, 17 August 2006 13:32
		Re: Removing equal elements from an array By: news.qwest.net on Thu, 17 August 2006 13:06
		Re: Removing equal elements from an array By: JD Smith on Thu, 17 August 2006 10:59
		Re: Removing equal elements from an array By: news.qwest.net on Thu, 17 August 2006 09:07
		Re: Removing equal elements from an array By: Julio[1] on Wed, 16 August 2006 12:42
		Re: Removing equal elements from an array By: R.Bauer on Wed, 13 September 2006 23:32

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