| Re: Finding duplicate values in an array [message #2582] |
Tue, 19 July 1994 12:12  |
andy
Messages: 31
Registered: November 1993
|
Member |
|
|
In article <30goug$bkp@nyx10.cs.du.edu>, slohmeie@nyx10.cs.du.edu (stephen lohmeier) writes:
> In article <1994Jul18.171646@chapman.gsfc.nasa.gov>,
> Ian Sprod <sprod@chapman.gsfc.nasa.gov> wrote:
>>
>> I seem to remember the topic of finding duplicate values in an array
>> was discussed some months ago, but i never did read the end of the thread.
>>
>> What is the _fastest_ way to throw duplicated values out?
>>
>> thanks
>>
>> ian
>
> This is how I'd do it:
>
> ;array of values
> arr = [.14, .11, .13, .12, .13, .13, .12, .13, .09, .13, .10, .12, .09, .14]
>
> ;sort array
> arr_sorted = arr(sort(arr))
>
> ;find disparity between adjacent elements
> n = n_elements(arr_sorted)
> disparity = arr_sorted(1:n-1)-arr_sorted(0:n-2)
>
> ;find locations where disparities are non-zero
> index = where(disparity)+1
>
> ;non-duplicated array
> arr_nodups = [arr_sorted(0), arr_sorted(index)]
>
> END
>
> Hope this helps.
>
>
How about this...
arr = [.14, .11, .13, .12, .13, .13, .12, .13, .09, .13, .10, .12, .09, .14]
arr_nodups = arr(uniq(arr,sort(arr)))
Andy
--
,__o Andrew F. Loughe (Mail Code 971)
-\_<, NASA Goddard Space Flight Center phone: (301) 286-5899
(*)/'(*) Greenbelt, MD 20771 email: andy.loughe@gsfc.nasa.gov
|
|
|
|
comp.lang.idl-pvwave archive
Members
Search
Help
Login
Home
