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#ifndef GMX_PBCUTIL_ISHIFT_H
#define GMX_PBCUTIL_ISHIFT_H

#define D_BOX_Z 1
#define D_BOX_Y 1
#define D_BOX_X 2
#define N_BOX_Z (2 * D_BOX_Z + 1)
#define N_BOX_Y (2 * D_BOX_Y + 1)
#define N_BOX_X (2 * D_BOX_X + 1)
#define N_IVEC (N_BOX_Z * N_BOX_Y * N_BOX_X)
#define CENTRAL (N_IVEC / 2)
#define SHIFTS N_IVEC

#define XYZ2IS(x, y, z) (N_BOX_X * (N_BOX_Y * ((z) + D_BOX_Z) + (y) + D_BOX_Y) + (x) + D_BOX_X)
#define IVEC2IS(iv) (XYZ2IS((iv)[XX], (iv)[YY], (iv)[ZZ]))
#define IS2X(iv) (((iv) % N_BOX_X) - D_BOX_X)
#define IS2Y(iv) ((((iv) / N_BOX_X) % N_BOX_Y) - D_BOX_Y)
#define IS2Z(iv) ((iv) / (N_BOX_X * N_BOX_Y) - D_BOX_Z)

#endif
