init
read seq protein.seq
read prot hcchcosyO1.prot

update atom GFT COSY_C
update atom GFT COSY_H
# or only update chemical shift for given atom type 

write prot hcchcosyO2.prot 

simulate 3D CA  COSY_CH  0 1 
simulate 3D CA  COSY_C   0 1

simulate 3D CB  COSY_CH  0 2 
simulate 3D CB  COSY_C   0 2

simulate 3D CG  COSY_CH  0 3 
simulate 3D CG  COSY_C   0 3
simulate 3D CG1 COSY_CH  0 3 
simulate 3D CG1 COSY_C   0 3
simulate 3D CG2 COSY_CH  0 3 
simulate 3D CG2 COSY_C   0 3

simulate 3D CD  COSY_CH  0 4 
simulate 3D CD  COSY_C   0 4
simulate 3D CD1 COSY_CH  0 4 
simulate 3D CD1 COSY_C   0 4
simulate 3D CD2 COSY_CH  0 4 
simulate 3D CD2 COSY_C   0 4

write peaks hcchcosyI2.peaks

