[modeller_usage] Question about chi dihedral angle cubic spline restraint

Dear all,

I have a question about chi dihedral angle in rsr (restraint) file.

The following is one of chi1 dihedral angles.

R 10 22 3 14 4 28 0 1 2 3 4 1.0000 -3.1416 3.1584 0.3000 0.1072 -1.8388 0.3519 0.5736 1.8270 4.1095 4.6770 1.6637 0.1167 0.0925 1.5911 4.6125 7.2224 6.4874 3.6210 1.5701 0.8375 1.4232 3.3272 6.1649 5.4708 2.8728 1.0891 0.3370

I think that the 14th and 15th columns (-3.1416 and 3.1584) represent the low and high points, respectively.

The chi angle should be periodic from -pi to pi radians, but two values do not agree with pi and -pi.

When I generated the spline function using these data and the values at pi and -pi seems to be disagreement.

Is there any reason of using -3.1416 and 3.1584 not pi and -pi?

Thanks,

-- Jinhyuk