The XYZ TO UVW Python function

[dinghanwang]

Howdy, thank you for explaining two systems, do you know any built Python function to transform, thank you!

[PauloCarvalhoRJ]

Hello,

Here's my implementation in C++ from here) which was an extension to 3D of this one:

    

	//Obtain the topological coordinates (IJK) of the cell that contains the location.
	uint i, j, k;
	if( ! XYZtoIJK( x, y, z, i, j, k ) )
		return false;

	//Obtain the index of the cell.
	uint cellIndex = IJKtoIndex( i, j, k );

	//Make a point object corresponding to the query location.
	Vertex3D location{ x, y, z };

	//Get the faces' geometries of the cell.
	std::vector<Face3D> cellFaces = getFaces( cellIndex );

	//faces 2 and 3 are along I direction, thus are respect to U depositional coordinate
	//faces 4 and 5 are along J direction, thus are respect to V depositional coordinate
	//faces 0 and 1 are along K direction, thus are respect to W depositional coordinate
	//compute the six distances between the location and the faces
	double dU0 = cellFaces[2].distance( location );
	double dU1 = cellFaces[3].distance( location );
	double dV0 = cellFaces[4].distance( location );
	double dV1 = cellFaces[5].distance( location );
	double dW0 = cellFaces[0].distance( location );
	double dW1 = cellFaces[1].distance( location );

	//compute the UVW within the cell (min = 0.0, max = 1.0)
	double local_u = dU0 / (dU0 + dU1);
	double local_v = dV0 / (dV0 + dV1);
	double local_w = dW0 / (dW0 + dW1);

	//compute the global UVW steps.
	double du = 1.0 / m_nI;
	double dv = 1.0 / m_nJ;
	double dw = 1.0 / m_nK;

	//compute the UVW coordinates.
	u = du * i + du * local_u;
	v = dv * j + dv * local_v;
	w = dw * k + dw * local_w;

    //enforcing sanity
    if( std::isfinite( u ) && std::isfinite( v ) && std::isfinite( w ) )
        return true;
    else
        return false;

Maybe this can help someone get started on a Python implementation.

best,

PC