question on vector an new

[mickey]

hi, I need to obtain a vector of arrays;
Is this correct? thanks

GLfloat* position = new GLfloat[4];
vector <GLfloat*> ppp;
for (int g=0; g < ....; g++) {
    for (int i=0; i<4; i++) {
	position[i] = ch.toInt(); // split a string as "1543"	
   }
 
   ppp.push_back(position);
}
 
  for( std::vector<GLfloat*>::iterator i = ppp.begin(); i != ppp.end(); ++i ) {
	delete [] *i;
   }	
   ppp.clear();

GLfloat* position = new GLfloat[4];
vector <GLfloat*> ppp;
for (int g=0; g < ....; g++) {
    for (int i=0; i<4; i++) {
	position[i] = ch.toInt(); // split a string as "1543"	
   }
     
   ppp.push_back(position);
}
   
  for( std::vector<GLfloat*>::iterator i = ppp.begin(); i != ppp.end(); ++i ) {
	delete [] *i;
   }	
   ppp.clear();

To copy to clipboard, switch view to plain text mode 

[jacek]

No, because you create and change only one array. In result ppp contains a number of pointers to that single array.

[mickey]

Right?

vector <GLfloat*> ppp;
  for (int g=0; g < ....; g++) {
      GLfloat* position = new GLfloat[4];
      for (int i=0; i<4; i++) {
            position[i] = ch.toInt(); // split a string as "1543"   
   }
    ppp.push_back(position);
   }
 
  for( std::vector<GLfloat*>::iterator i = ppp.begin(); i != ppp.end(); ++i ) {
    delete [] *i;
   }    
   ppp.clear();

vector <GLfloat*> ppp;
  for (int g=0; g < ....; g++) {
      GLfloat* position = new GLfloat[4];
      for (int i=0; i<4; i++) {
            position[i] = ch.toInt(); // split a string as "1543"   
   }
    ppp.push_back(position);
   }
   
  for( std::vector<GLfloat*>::iterator i = ppp.begin(); i != ppp.end(); ++i ) {
    delete [] *i;
   }    
   ppp.clear();

To copy to clipboard, switch view to plain text mode 

and how obtain value of fist element array of first element vector?? thanks

[jacek]

Right?

Now it looks OK.

and how obtain value of fist element array of first element vector?? thanks

GLfloat f = ppp[0][0];
// or 
GLfloat f = ppp.at( 0 )[ 0 ];

GLfloat f = ppp[0][0];
// or 
GLfloat f = ppp.at( 0 )[ 0 ];

To copy to clipboard, switch view to plain text mode 

http://www.cppreference.com/cppvector/at.html