Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Library: xclust
See also: xfcme xchcme

Quantlet: xcfcgk
Description: performs a fuzzy Gustafson-Kessel cluster analysis.

Reference(s):

Usage: {v,d,uu}=xcfcme(x,c,m,e)
Input:
x n x p matrix of n row points to be clustered
c scalar representing the number of clusters
m scalar, determines the fuzziness of clustering (m>1)
e scalar, termination tolerance
Output:
v p x p matrix of cluster centers
d n x p matrix of distances
uu n x p matrix of result

Example:
proc(xx,yy1,yy2)=idxgraph(out,x)
  xx=matrix(max(x[,1])+1)*0
  yy1=xx
  yy2=xx
  i=1
  while(i <= max(x[,1])+1)
    xx[i]= i-1
    yy1[i]= max(paf(out.uu'[,1], x[,1]==i-1))
    yy2[i]= max(paf(out.uu'[,2], x[,1]==i-1))
    i=i+1
  endo
endp
library("xclust")
library("plot")
z=read("butterfly")
x=z[,2:3]
c=2
m=2
e=0.01
out=xcfcgk(x,c,m,e)      //apply fuzzy gustafson-kessel clustering
out.uu'
tt=idxgraph(out,x)
tyy1=tt.xx~tt.yy1
tyy2=tt.xx~tt.yy2
tyy1 = setmask(tyy1, "line", "red", "thin")
tyy2 = setmask(tyy2, "line", "blue", "medium")
disp = createdisplay(1,1)
show(disp,1,1, tyy1, tyy2)
strm = string("%1.0f", m)
setgopt(disp,1,1, "title","Membership Function for Fuzzy GK with m="+ strm)

Result:
gives the partitions of membership functions and depicts
this membership function for m = 2.



Author: H. Sofyan, 20020114
(C) MD*TECH Method and Data Technologies, 05.02.2006