reverseAccess( index ) {

		const z = Math.floor( index / ( this.yLength * this.xLength ) );
		const y = Math.floor( ( index - z * this.yLength * this.xLength ) / this.xLength );
		const x = index - z * this.yLength * this.xLength - y * this.xLength;
		return [ x, y, z ];

	}
Retrieve the IJK coordinates of the voxel corresponding of the given index in the data.

@param {number} index - Index of the voxel.
@returns {Array<number>} The IJK coordinates as `[x,y,z]`.