• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Liutauras Vilda
  • Bear Bibeault
  • Jeanne Boyarsky
  • Tim Cooke
Sheriffs:
  • Knute Snortum
  • Junilu Lacar
  • Devaka Cooray
Saloon Keepers:
  • Ganesh Patekar
  • Tim Moores
  • Carey Brown
  • Stephan van Hulst
  • salvin francis
Bartenders:
  • Ron McLeod
  • Frits Walraven
  • Pete Letkeman

Sorting question.  RSS feed

 
Greenhorn
Posts: 26
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hello all,

There is a simple way to sort in java using Arrays.sort. However, is there anyway i can get an array of indexes which tells me whats the old position of that sorted element? For people who have used Matlab ( [sortval sortpos] = sort(z,'ascend') ), its the sortpos matrix.

for example:-
z = [ 1 10 2 5 4 ]
When you sort you get:-
z_sorted = [ 1 2 4 5 10 ]
I also need an array like this:-
indexs = [ 1 3 5 4 2 ]

I know i can do some post processing on the sorted array to get this, however i was wondering if there is some inbuilt way in java (or some really quick way) of doing this.

Thanks in advance'
Neville
 
Sheriff
Posts: 21504
96
Chrome Eclipse IDE Java Spring Ubuntu VI Editor Windows
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
This exact same question has come up last week or so: http://www.coderanch.com/t/451158/Java-General-beginner/java/Helping-Sorting-Array-Doubles-But
 
It is sorta covered in the JavaRanch Style Guide.
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!