Removing duplicate values in 2d array

Question

0.00/5 (No votes)

See more:

i have 5700 rows and 3 columns of 2d array.
have to eliminate the repeated row from that array and print only one row out of multiple repeated rows.
count=5700.
for example,

24.742235	0.005334	0.052465	
27.345229	-0.222687	0.266042	
27.345229	-0.222687	0.266042	
25.528389	-0.063540	0.117000	
24.742235	0.005334	0.052465	
25.528389	-0.063540	0.117000	
24.742235	0.005334	0.052465	
25.528389	-0.063540	0.117000	
24.742235	0.005334	0.052465	
25.528389	-0.063540	0.117000	
27.345229	-0.222687	0.266042	
24.742235	0.005334	0.052465	
27.345229	-0.222687	0.266042	
25.528389	-0.063540	0.117000	
25.528389	-0.063540	0.117000	
27.345229	-0.222687	0.266042	
27.345229	-0.222687	0.266042	
24.742235	0.005334	0.052465	
24.742235	0.005334	0.052465	
27.345229	-0.222687	0.266042

What I have tried:

for(p=0;p<count;p++)
{
for(ppp=p+1;ppp<count;ppp++)
{
if(plane[ppp][1]!=plane[p][1])
{
printf("%lf\t%lf\t%lf\n",plane[p][0],plane[p][1],plane[p][2]);
printf("%lf\t%lf\t%lf\n",plane[ppp][0],plane[ppp][1],plane[ppp][2]);
}
}
}

Posted 27-Feb-17 19:34pm

R!sh!

Updated 27-Feb-17 22:24pm

Add a Solution

3 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Accepted Answer · 2017-02-27T20:03:00

Solution 1

If you want to remove all duplicates, so you are left with the distinct rows only, then the simplest way if to sort the input, so that duplicates are next to each other.
that way, it's trivial to remove duplicated rows.

C and C++ both include library routines to sort an array.

Posted 27-Feb-17 20:03pm

OriginalGriff

Comments

R!sh! 28-Feb-17 5:51am

can you give the logic for sorting that type of array?

OriginalGriff 28-Feb-17 6:06am

Look at the "standard" C library qsort - you call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function. You write the function, which is given two pointers to your data elements to compare.

R!sh! 1-Mar-17 23:40pm

okk thank you

CPallini · Accepted Answer · 2017-02-27T22:24:00

Taking advantage of the C++ library, you may use the std::set class. For instance:

C++

#include <iostream>
#include <set>
using namespace std;


struct DataInfo
{
  double d[3];

  bool operator()( const DataInfo & dia, const DataInfo & dib) const
  {
    for (size_t n=0; n<3; ++n)
    {
      if ( dia.d[n] < dib.d[n] ) return true;
      if ( dia.d[n] > dib.d[n] ) return false;
    }
    return false;
  }
};

int main()
{
  set <DataInfo, DataInfo> sdi;

  for (;;)
  {
    DataInfo di;
    cin >> di.d[0] >> di.d[1] >> di.d[2];
    if ( cin.eof()) break;
    sdi.insert(di);
  }


  for (const auto & di : sdi)
    cout << di.d[0] << " " << di.d[1] << di.d[2] << endl;
}

Jochen Arndt · Accepted Answer · 2017-02-27T22:16:00

A solution that does not change the order (untested):

/* Print first item */
printf("%lf\t%lf\t%lf\n",plane[0][0],plane[0][1],plane[0][2]);
for(p=1;p<count;p++)
{
    /* Check if a duplicate (already printed) */
    for(ppp=0;ppp<p;ppp++)
    {
        if(plane[p][1]==plane[ppp][1])
            break;
    }
    /* Not a duplicate if above loop not terminated */
    if (p >= ppp)
        printf("%lf\t%lf\t%lf\n",plane[p][0],plane[p][1],plane[p][2]);
}

Removing duplicate values in 2d array

3 solutions

Solution 1

Solution 3

Solution 2

Add your solution here

Preview 0