# coding: utf-8

# MDTraj provides convenience functions for predicting various NMR observables such as chemical shifts.  To do this, we provide wrapper functions for the SPARTA+, PPM, and ShiftX2 prediction algorithms.  

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get_ipython().magic(u'matplotlib inline')
import mdtraj as md


# Let's load a simple trajectory containing three identical frames of the villin headpiece protein.

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trj = md.load("1vii_3frames.pdb")


# Now, let's calculate the chemical shifts with the program SPARTA+.

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shifts = md.nmr.chemical_shifts_spartaplus(trj)
shifts[0:10]


# The data is returned as a Pandas Dataframe object. The rows correspond to the residue numbers and atom names, while each column corresponds to a different frame in your trajectory.  Note that here our input had completely identical conformations in each frame, so we see identical values along each row.

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