Home > wafo > trgauss > nt2fr.m

nt2fr

PURPOSE ^

Calculates the frequency matrix given the counting distribution matrix.

SYNOPSIS ^

F=nt2fr(M,def)

DESCRIPTION ^

 NT2FR  Calculates the frequency matrix given the counting distribution matrix. 
  
   CALL: fr = nt2fr(NT); 
         fr = nt2fr(NT,def); 
  
   where 
  
         fr  = the frequency matrix, 
         NT  = the counting distribution matrix, 
         def = 0,1 
         k   = number of diagonals from main diagonal to be 
               set to zero (optional input argument). 
  
   If def=0 function computes the inverse to  
  
      N_T(u,v) = #{ (M_i,m_i); M_i>u, m_i<v } 
  
   and if def=1 the inverse to 
  
      N_T(u,v) = #{ (M_i,m_i); M_i>=u, m_i=<v } 
  
   where  (M_i,m_i)  are  cycles and v,u are in the discretization grid.

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

001 function F=nt2fr(M,def) 
002 %NT2FR  Calculates the frequency matrix given the counting distribution matrix. 
003 % 
004 %  CALL: fr = nt2fr(NT); 
005 %        fr = nt2fr(NT,def); 
006 % 
007 %  where 
008 % 
009 %        fr  = the frequency matrix, 
010 %        NT  = the counting distribution matrix, 
011 %        def = 0,1 
012 %        k   = number of diagonals from main diagonal to be 
013 %              set to zero (optional input argument). 
014 % 
015 %  If def=0 function computes the inverse to  
016 % 
017 %     N_T(u,v) = #{ (M_i,m_i); M_i>u, m_i<v } 
018 % 
019 %  and if def=1 the inverse to 
020 % 
021 %     N_T(u,v) = #{ (M_i,m_i); M_i>=u, m_i=<v } 
022 % 
023 %  where  (M_i,m_i)  are  cycles and v,u are in the discretization grid. 
024 % 
025  
026  
027 n=length(M); P=zeros(size(M)); 
028  
029 if nargin<2 
030 def=0; 
031 end 
032  
033 if def==0 
034 P(1:n-1,1:n-1)=M(1:n-1,1:n-1)+M(2:n,2:n)-M(1:n-1,2:n)-M(2:n,1:n-1); 
035 else 
036 P(2:n,2:n)=M(1:n-1,1:n-1)+M(2:n,2:n)-M(1:n-1,2:n)-M(2:n,1:n-1); 
037 end 
038  
039 %if nargin==2 
040 %  k_cut=k; 
041 %else 
042 %  k_cut=2; 
043 %end   
044  
045 F=P; 
046  
047 %F=fliplr(triu(fliplr(P),k_cut)); 
048  
049  
050

Mathematical Statistics
Centre for Mathematical Sciences
Lund University with Lund Institute of Technology

Comments or corrections to the WAFO group


Generated on Thu 06-Oct-2005 02:21:16 for WAFO by m2html © 2003