File: linearlt.cat

package info (click to toggle)
scilab 2.4-1
  • links: PTS
  • area: non-free
  • in suites: potato, slink
  • size: 55,196 kB
  • ctags: 38,019
  • sloc: ansic: 231,970; fortran: 148,976; tcl: 7,099; makefile: 4,585; sh: 2,978; csh: 154; cpp: 101; asm: 39; sed: 5
file content (47 lines) | stat: -rw-r--r-- 1,305 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47

linearlt(2)                    Scilab Function                    linearlt(2)
NAME
   linearlt -  linear time legendre transform

  Author: Christophe Canus

  This C_LAB routine the Legendre transform of a function using the linear
  time Legendre transform algorithm.

Usage
  [s,u_star_s]=linearlt(x,u_x)

Input parameters
       o x : real vector [1,N] or [N,1] Contains the abscissa.
       o y : real vector [1,N] or [N,1] Contains the function to be
         transformed.
Output parameters
       o s : real vector [1,M] Contains the abscissa of the regularized func-
         tion.
       o u_star_s : real vector [1,M] Contains the Legendre conjugate func-
         tion.
Description

Parameters
  The abscissa x and the function u_x  to be transformed must be of the same
  size [1,N] or [N,1].  The abscissa s and the Legendre conjugate function
  u_star_s are of the same size [1,M] with M<=N.

Algorithm details
  The linear time Legendre transform algorithm is based on  the use of a con-
  cave regularization before slopes' computation.
Examples

Matlab

  x=linspace(-5.,5.,1024);
  u_x=-1+log(6+x);
  plot(x,u_x);
  % looks like a Reyni exponents function, isn't it ?
  [s,u_star_s]=linearlt(x,u_x);
  plot(s,u_star_s);
Scilab

  //
References
  None..SH See Also bbch (C_LAB routine).