title: Algorithms for finding the axis of a helix: fast rotational and parametric least-squares methods.
abstract: Several methods for finding the axis of a helix are presented and compared. The most accurate determines the helix axis as the axis of rotation necessary to map point i to point i + 1 of the helix. The fastest method calculates the helix axis as the best-fit line through the coordinates by a three-dimensional parametric linear least-squares algorithm, taking advantage of the sequential nature of the data.
authors.affiliation: Department of Biochemistry & Biophysics, Texas A&M University 77843-2128, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Christopher
authors.forename: R
authors.initials: R
authors.lastname: Swanson
authors.forename: T O
authors.initials: TO
authors.lastname: Baldwin
mesh_terms: D000465:Algorithms; D003201:Computers; D004247:DNA / Q000737:chemistry*; D016018:Least-Squares Analysis; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry*; D012399:Rotation
chemical_list: D011506:Proteins; D004247:DNA