NMRWish Built-In TCL Functions
dynGetNAAngles: Get angles from a Nucleic Acid structure.

Flag	Argument	Default	Description
`-src`	`ptrVal`	`None`	Source of Structure Data.
`-res`	`resList`	`None`	Residue ID List.
`-chain`	`cName`	`*`	Chain Name.
`-seg`	`sName`	`*`	Seg Name.

Returns 12 Angles per Residue:
alpha beta gamma delta epsilon zeta chi v0 v1 v2 v3 v4
Backbone and Glycosidic Torsions:

 1. alpha(i):     O3'(i-1) P(i)   O5'(i) C5'(i)
 2. beta(i):      P(i)     O5'(i) C5'(i) C4'(i)
 3. gamma(i):     O5'(i)   C5'(i) C4'(i) C3'(i)
 4. delta(i):     C5'(i)   C4'(i) C3'(i) O3'(i)
 5. epsilon(i):   C4'(i)   C3'(i) O3'(i) P(i+1)
 6. zeta(i):      C3'(i)   O3'(i) P(i+1) O5'(i+1)
 7. chi(i) A,G:   C4'(i)   C1'(i) N9(i)  C4(i)
 8. chi(i) C,U,T: C4'(i)   N1(i)  N9(i)  C2(i)

Sugar Torsion Angles:

 1. v0(i): C4'(i) O4'(i) C1'(i) C2'(i)
 2. v1(i): O4'(i) C1'(i) C2'(i) C3'(i)
 3. v2(i): C1'(i) C2'(i) C3'(i) C4'(i)
 4. v3(i): C2'(i) C3'(i) C4'(i) O4'(i)
 5. v4(i): C3'(i) C4'(i) O4'(i) C1'(i)

Frank Delaglio, Ph.D.