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copied!<p>Since non of the answers worked for me, I made my own class. The class works well for me. But I am pretty sure it is not designed so C++'y. It also may result in memory leaks. If you found a problem with it, please leave me a comment. I'd upgrade the code if I made a new version to keep the answer useful for others. By the way, the class works for 1, 2, and 3 dimensions now, but it can be easily extended to any number of dimensions. Here is the code,</p> <pre><code>#ifndef XARRAY_H_INCLUDED #define XARRAY_H_INCLUDED #include <string> #include <sstream> #include <vector> #include <assert.h> using namespace std; template <class T = double> class XArray { // Fields (keep data) int index_helper[10]; // cells of the array vector<T> table; // dimensions of the array vector<int> dims; public: XArray(){} XArray(unsigned int n, int *d) { dims.resize(n); int size = 1; for (unsigned int i = 0; i < n; i++) { size *= d[i]; dims[i] = d[i]; } table.resize(size); } XArray(unsigned int d1) { dims.resize(1); dims[0] = d1; table.resize(d1); } XArray(unsigned int d1, unsigned int d2) { dims.resize(2); dims[0] = d1; dims[1] = d2; table.resize(d1 * d2); } XArray(unsigned int d1, unsigned int d2, unsigned int d3) { dims.resize(3); dims[0] = d1; dims[1] = d2; dims[2] = d3; table.resize(d1 * d2 * d3); } XArray(const XArray<T>& xa) { this->table = xa.table; this->dims = xa.dims; } int dim(int i) { return dims[i]; } int num_dims() { return dims.size(); } T& operator()(int i) { index_helper[0] = i; return get_helper(1, index_helper); } T& operator()(int i, int j) { index_helper[0] = i; index_helper[1] = j; return get_helper(2, index_helper); } T& operator()(int i, int j, int k) { index_helper[0] = i; index_helper[1] = j; index_helper[2] = k; return get_helper(3, index_helper); } XArray<T> operator*(double m) { XArray<T> r = *this; for (unsigned int i = 0; i < table.size(); i++) { r.table[i] *= m; } return r; } XArray<T> operator/(double m) { XArray<T> r = *this; for (unsigned int i = 0; i < table.size(); i++) { r.table[i] /= m; } return r; } XArray<T> operator+(const XArray<T> &that) { assert(this->dims.size() == that.dims.size()); for (unsigned int i = 0; i < dims.size(); i++) { assert(this->dims[i] == that.dims[i]); } XArray<T> r = *this; for (unsigned int i = 0; i < table.size(); i++) { r.table[i] += that.table[i]; } return r; } XArray<T> operator-(const XArray<T> &that) { assert(this->dims.size() == that.dims.size()); for (unsigned int i = 0; i < dims.size(); i++) { assert(this->dims[i] == that.dims[i]); } XArray<T> r = *this; for (unsigned int i = 0; i < table.size(); i++) { r.table[i] -= that.table[i]; } return r; } private: T& get_helper(unsigned int n, int *indices) { assert(n == dims.size()); int multiplier = 1; int index = 0; for (unsigned int i = 0; i < n; i++) { //cerr << "index " << i << " out of range. Expected [0, " << dims[i] - 1 // << "] found " << indices[i] << endl; assert(indices[i] >= 0 && indices[i] < dims[i]); index += indices[i] * multiplier; multiplier *= dims[i]; } return table[index]; } }; template <class T> ostream &operator<<(ostream &stream, XArray<T> xa) { int d = xa.num_dims(); if(d == 1) { int n = xa.dim(0); for(int i = 0; i < n; i++) { stream << xa(i); if(i < n - 1) { stream << ", "; } } } else { stream << "XArray["; for(int i = 0; i < d; i++) { stream << xa.dim(i); if(i < d - 1) { stream << "x"; } } stream << "]"; } return stream; } #endif // XARRAY_H_INCLUDED </code></pre>

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