Structure
The NOVAS library provides three levels of subroutines (functions): basic, utility, and supervisory. Basic-level subroutines supply the values of fundamental variables, such as the nutation angles and the heliocentric positions of solar system bodies for specific epoches. Utility-level subroutines perform transformations, such as those caused by precession, nutation and aberration. Supervisory-level subroutines serve as interfaces to the basic and utility subroutines to compute the coordinates of stars or solar system bodies for specific dates and times.
Read more about this topic: Naval Observatory Vector Astrometry Subroutines
Famous quotes containing the word structure:
“Just as a new scientific discovery manifests something that was already latent in the order of nature, and at the same time is logically related to the total structure of the existing science, so the new poem manifests something that was already latent in the order of words.”
—Northrop Frye (b. 1912)
“In the extent and proper structure of the Union, therefore, we behold a republican remedy for the diseases most incident to republican government.”
—James Madison (1751–1836)
“What is the most rigorous law of our being? Growth. No smallest atom of our moral, mental, or physical structure can stand still a year. It grows—it must grow; nothing can prevent it.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)