Re: overloading the [] operator in a vector child class
On 27 mrt, 11:02, "Erik Wikstr=F6m" <eri...@student.chalmers.se> wrote:
On 27 Mar, 10:36, "y-man" <ygra...@gmail.com> wrote:
Hi,
I am creating a child class of the vector, which contains a couple of
functions to make the work with carthesian coordinate vectors easier.
To make things work more easily, I would like to be able to access the
vector through a string which is either x, y or z. So that I can use:
---xyzvec.hh--
#ifndef XYZVEC_HH
#define XYZVEC_HH
#include <vector>
#include <iostream>
xyzvec vec ;
vec["x"] = 3;
double testing = vec["x"].
My class is now:
class xyzvec : public vector<double> {
public:
xyzvec( void ) : vector<double>(3) { }
xyzvec(double x, double y, double z) : vector<double>(3) {
(*this)[0] = x;
(*this)[1] = y;
(*this)[2] = z;
}
double x() { return (*this)[0] ; }
double y() { return (*this)[1] ; }
double z() { return (*this)[2] ; }
double length( void ) {
double n = pow(pow((*this)[0],2) + pow((*this)[1],2) + pow((*this)
[2],2),0.5) ;
return n;
}
double& operator[] (const string&) {
if(string=="x") return &(*this)[0] ;
if(string=="y") return &(*this)[0] ;
if(string=="z") return &(*this)[0] ;}
private:
} ;
#endif
---
Probably I am doing something horribly wrong with the pointers, but
this yields a big heap of errors.
I'm not an expert on inheritance but I don't think it works the way
you want to with the standard containers, try instead to keep a vector
as a member.
--
Erik Wikstr=F6m
It seems to work when I overload the "*"-operator... Is that a
different thing then?
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