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working with matrix and header

beccotrat (4)
Hi guys!

I'm a c++ beginner working on ArcGis derived .asc data, with the follow form:

ncols 572
nrows 375
xllcorner 614271.24923309
yllcorner 108824.59085717
cellsize 2
NODATA_value -9999
-9999 -9999 -9999 123.34 121.23 ...
...

I need to make calculation with that kind of matrix, reporting the header in a new file, and considering ncols and nrows automatically as maxi and maxj, and using celssize and NODATA_value as constant. Than make calculation on the matrix (example calue ij * cellsize) and copy the result under the header of the new file. I can use the matrix alone, but I havent idea on how working with the header (note the problem of the variable number of tabs...).
Someone can help me?

Thank's!

Gabriele
PanGalactic (1658)
Search this site for "xllcorner" (it is suitably unique to ArcGIS) and you will find examples of code for working ArcGIS data.
beccotrat (4)
Thank's for your suggest and sorry for the disturb! I find some interesting solution and I'm triing!
beccotrat (4)
I just try to follow indication, but I have already some problem...
I can work on the header of the matrix file, but I have many problems with the matrix. I try to do 2 codes using indication find in the forum. I need to copy the header of the matrix in the result .txt file, and after that read each i-j double varaible, and if it isn't noData add to it 10 (it is a try), and than copy on the right place in the same result.txt file, under the header.
First one will be the quicly one:

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#include <fstream>
#include <string>
#include <iostream>
#include <iomanip>
#include <iterator>
#include <sstream>
#include <deque>
#include <vector>

using namespace std;

typedef vector <float>     container;
typedef deque  <container> container2;
int ncols, nrows, nodataValue;
double xllcorner, yllcorner, size;
typedef double matrice [1437][1681];
void scrivi ()
{
	string s;
	cout << "dati georiferiti" << "\n";
	ifstream ifs ("D:\\projects\\tesaf\\programmazione\\prova.txt");
	ofstream ofs ("D:\\projects\\tesaf\\programmazione\\demout.txt", ios_base::trunc);
	for (int i=0; i<6; i++)
	{
		getline (ifs, s);
		ofs << s << endl;
	}
	ifs.close ();
	ofs.close ();
}
void ricon()
{
	string s1;
	ifstream ifs1 ("D:\\projects\\tesaf\\programmazione\\prova.txt");
	ifs1 >> s1 >> ncols;
	ifs1 >> s1 >> nrows;
	ifs1 >> s1 >> xllcorner;
	ifs1 >> s1 >> yllcorner;
	ifs1 >> s1 >> size;
	ifs1 >> s1 >> nodataValue;
	cout << "ncols" << ncols << "\n";
	cout << "nrows" << nrows << "\n";
	cout << "xllcorner" << xllcorner << "\n";
	cout << "yllcorner" << yllcorner << "\n";
	cout << "size" << size << "\n";
	cout << "nodataValue" << nodataValue << "\n";
	ifs1.close ();
	cout << "fine elaborazione";
	cout << endl << endl;
}

void load_at_once( const char* filename, string& result )
  {
  ifstream f( "D:\\projects\\tesaf\\programmazione\\prova.txt", ios::binary );
  result.assign( istream_iterator <char> ( f ), istream_iterator <char> () );
  }

struct data_t
  {
  unsigned nrows;
  unsigned ncols;
  double   xllcorner;
  double   yllcorner;
  int      cellsize;
  double   nodatavalue;

  container2 data;
  };

void load_in_pieces( istream& f, data_t& data )
  {
ofstream ofs2 ("D:\\projects\\tesaf\\programmazione\\demout.txt", ios_base::trunc);
double r;
string s;
  f >> s >> data.ncols
    >> s >> data.nrows
    >> s >> data.xllcorner
    >> s >> data.yllcorner
    >> s >> data.cellsize
    >> s >> data.nodatavalue;
  data.data.resize( data.nrows );
  for (container2::iterator row = data.data.begin(); row != data.data.end(); ++row)
    {
    row->resize( data.ncols );
    for (container::iterator col = row->begin(); col != row->end(); ++col)
      {
      f >> *col;
	  if (*col == data.nodatavalue)
	  {
		  ofs2 << *col;
	  }
	  else
	  {
	r= *col+10;
	ofs2 << *col;
	  }
      }
	ofs2.close();
    }
  }

int main ()
{
	string raw_data;
	data_t data;
	cout << "\aparti";
	scrivi();
	ricon();
	load_at_once ("D:\\projects\\tesaf\\programmazione\\prova.txt", raw_data);
	istringstream iss (raw_data);
	load_in_pieces (iss, data);
	cout << "fine elaborazione";
	cout << endl << endl;
	system ("pause");
	return 0;
}

the second should be more easy to realize, but a little slower:

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#include <fstream>
#include <string>
#include <iostream>
#include <iomanip>
#include <iterator>
#include <sstream>
#include <vector>
#include <deque>
using namespace std;
int ncols, nrows, nodataValue;
double xllcorner, yllcorner, size;
string line;
void scrivi ()
{
	string s;
	cout << "dati georiferiti" << "\n";
	ifstream ifs ("D:\\projects\\tesaf\\programmazione\\prova.txt");
	ofstream ofs ("D:\\projects\\tesaf\\programmazione\\demout.txt", ios_base::trunc);
	for (int i=0; i<6; i++)
	{
		getline (ifs, s);
		ofs << s << endl;
	}
	ifs.close ();
	ofs.close ();
}
void ricon()
{
	string s1;
	ifstream ifs1 ("D:\\projects\\tesaf\\programmazione\\prova.txt");
	ifs1 >> s1 >> ncols;
	ifs1 >> s1 >> nrows;
	ifs1 >> s1 >> xllcorner;
	ifs1 >> s1 >> yllcorner;
	ifs1 >> s1 >> size;
	ifs1 >> s1 >> nodataValue;
	cout << "ncols" << ncols << "\n";
	cout << "nrows" << nrows << "\n";
	cout << "xllcorner" << xllcorner << "\n";
	cout << "yllcorner" << yllcorner << "\n";
	cout << "size" << size << "\n";
	cout << "nodataValue" << nodataValue << "\n";
	ifs1.close ();
	cout << "fine elaborazione";
	cout << endl << endl;
}
void elaborazione ()
{
	vector<vector<double>> data;
	ifstream ifs2 ("D:\\projects\\tesaf\\programmazione\\prova.txt");
	ofstream ofs2 ("D:\\projects\\tesaf\\programmazione\\demout.txt", ios_base::ate);
if (ncols * nrows > 0)
		{		
			// Set up sizes. (rows x cols)
			data.resize(nrows);
			for (unsigned row = 0; row < nrows; ++row)
			{
				data[row].resize(ncols);
			}

			// Load values in	
			double quota;
			unsigned row = 0;
			while (row < nrows)
			{							
				getline(ifs2, line);
				istringstream ss (line);
				for (unsigned col =0; col < ncols; col++)
				{
					ss >> data[row][col];
					ss>>quota;
				}
				if (quota == nodataValue)
			{
			  ofs2 << quota;
			}
		else
		{
		quota = quota+10;
		ofs2 << quota;
		 }
				row ++;
			}
			ifs2.close();	
			}
		ifs2.close ();
		ofs2.close ();
}
int main ()
{
	cout << "\aparti";
	scrivi();
	ricon();
	elaborazione ();
	cout << "fine elaborazione";
	cout << endl << endl;
	system ("pause");
	return 0;

}



The problem is that noone work... someone can help me?
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