curvd(3NCARG)
NAME
CURVD - derivatives for 1D functions.
SYNOPSIS
FUNCTION CURVD (T, N, X, Y, YP, SIGMA) This function calculates a derivative at a specified point using a spline under tension. CURV1 must be called prior to calling CURVD, and the values thus obtained used as input to CURVD. The derivative value is returned.
DESCRIPTION
T (real, input) The abscissa for which an interpolated
function value is desired.
N (integer, input) The number of input data values. (N > 1)
X (real, input) An array containing the abscissae for the
input function.
Y (real, input) An array containing the functional values of
the input data -- Y(K) is the functional value at X(K) for
K=1,N.
YP (real, input) Contains values for the second derivative (as
calculated by CURV1).
SIGMA (real, input) Tension factor. Values near zero result in a
cubic spline; large values (e.g. 50) result in nearly a
polygonal line. A typical value is 1.
RETURN VALUE
CURVD returns the derivative value of the interpolated curve at the specified point T.
ACCESS
To use CURVD, load the NCAR Graphics library ngmath.
SEE ALSO
curv1, fitgrid_params. Complete documentation for Fitgrid is available at URL http://ngwww.ucar.edu/ngdoc/ng/ngmath/fitgrid/fithome.html
COPYRIGHT
Copyright (C) 2000 University Corporation for Atmospheric Research The use of this Software is governed by a License Agreement.
Opportunity
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
Free Books
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Education
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.
