create matrix from csv (help)

[adicahyanto]

int OnInit()
  {
//---
//start write the file
   filehandle=FileOpen("ABC_Test.csv",FILE_WRITE|FILE_CSV);
   //check if any error
   if(filehandle!=INVALID_HANDLE)
     {      
      Print("File opened correctly");
     }
   else Print("Error in opening file,",GetLastError());
   //write file
   for(int i=0;i<10;i++)
     {
         FileWrite(filehandle,"0.5","0.01","0.43","0.22","0.65"
               );
     }

   FileClose(filehandle);
//---
   return(INIT_SUCCEEDED);
  }
//+------------------------------------------------------------------+
//| Expert deinitialization function                                 |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
//---
   filehandle=FileOpen("ABC_Test.csv",FILE_READ|FILE_CSV);

   matrix   mat_X  =  matrix.FromFile(10,5,filehandle,-1,0);

   Print(mat_X);

//---
  }

hi guys, i want to create a matrix from a csv file,

i've read the documentation here :

https://www.mql5.com/en/docs/basis/types/matrix_vector

i try to use the FromFile method but when i try to compile, it came out error "FromFile" undeclared identifier.

could somebody explain me more please?

---------------------------

then i'm trying to import manually from csv to matrix as code below:

void OnDeinit(const int reason)
  {
//---
   filehandle=FileOpen("ABC_Test.csv",FILE_READ|FILE_CSV);
   
   if(filehandle!=INVALID_HANDLE)
     {      
      Print("File opened correctly");
     }
   else Print("Error in opening file,",GetLastError());
   
   int   cols = 0, rows = 0;
   while(!FileIsEnding(filehandle))
     {
         mat_.Resize(rows+1,cols+1);
         data  =  FileReadString(filehandle);
         mat_[rows,cols] =  (double(data));
         cols++;
         Print(data);
         
         if(FileIsLineEnding(filehandle))
           {
               rows++;
               cols  =  0;
           }
     }
     

   Print(mat_);



//---
  }

but the printed out of data and the printed out of matrix mat_ show different result. could you please pointing me out where did i miss.

thanks

[adicahyanto]

adicahyanto:

hi guys, i want to create a matrix from a csv file,

i've read the documentation here :

https://www.mql5.com/en/docs/basis/types/matrix_vector

i try to use the FromFile method but when i try to compile, it came out error "FromFile" undeclared identifier.

could somebody explain me more please?

---------------------------

then i'm trying to import manually from csv to matrix as code below:

but the printed out of data and the printed out of matrix mat_ show different result. could you please pointing me out where did i miss.

thanks

found it.

what its need to be done is just by adding another finalcols, finalrows variables and then do matrix.Resize one again after the while loop.

int   cols = 0, rows = 0, fcols = 0, frows = 0;
                  string   data;
                  while(!FileIsEnding(fhandle))
                    {         
                        data  =  FileReadString(fhandle);
                        if(rows == 0)
                          {
                              mtx.Resize(rows+1,cols+1);
                          }
                        
                        mtx[rows,cols] =  (double(data));
                        cols++;
                        
                        if(FileIsLineEnding(fhandle))
                          {
                              fcols = cols;
                              rows++;
                              cols  =  0;
                              mtx.Resize(rows+1,fcols);
                          }
                     }
                  
                  frows =  rows;     
                  mtx.Resize(frows,fcols);

[Omega J Msigwa]

Here is the simple function to do it https://www.mql5.com/en/articles/11858#matrix-from-csv