scilab/modules/m2sci/macros/sci_files/sci_eig.sci

   1 // Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
   2 // Copyright (C) 2002-2004 - INRIA - Vincent COUVERT
   3 //
   4 // This file must be used under the terms of the CeCILL.
   5 // This source file is licensed as described in the file COPYING, which
   6 // you should have received as part of this distribution.  The terms
   7 // are also available at
   8 // http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt
   9
  10 function [tree]=sci_eig(tree)
  11 // M2SCI function
  12 // Conversion function for Matlab eig()
  13 // Input: tree = Matlab funcall tree
  14 // Ouput: tree = Scilab equivalent for tree
  15 // Emulation function: mtlb_eig()
  16
  17 // eig(A)
  18 if rhs==1 then
  19   // Because %c_spec and %b_spec are not defined
  20   A = getrhs(tree)
  21   A = convert2double(A)
  22   tree.rhs=Rhs_tlist(A)
  23
  24   // d = eig(A)
  25   if lhs==1 then
  26     tree.name="spec"
  27     tree.lhs(1).dims=list(A.dims(1),1)
  28     tree.lhs(1).type=Type(Double,Unknown)
  29   // [V,D] = eig(A)
  30   else
  31     set_infos(msprintf(gettext("mtlb_eig() called because Scilab and Matlab value do not always match for %s."),tree.lhs(1).name),0)
  32     tree.name="mtlb_eig"
  33     tree.lhs(1).dims=list(A.dims(1),A.dims(1))
  34     tree.lhs(1).type=Type(Double,Unknown)
  35     tree.lhs(2).dims=list(A.dims(1),A.dims(1))
  36     tree.lhs(2).type=Type(Double,Unknown)
  37   end
  38 // eig(A,B) or eig(A,'nobalance')
  39 elseif rhs==2 then
  40   [A,B] = getrhs(tree)
  41
  42   // 'nobalance'
  43   if B.vtype==String then
  44     no_equiv(gettext("''nobalance'' option, IGNORED."))
  45     tree.rhs=Rhs_tlist(tree.rhs(1))
  46     if lhs==1 then
  47       tree.name="spec"
  48       tree.lhs(1).dims=list(A.dims(1),1)
  49       tree.lhs(1).type=Type(Double,Unknown)
  50     else
  51       tree.rhs(1)=Operation("+",list(tree.rhs(1),Variable("%i",Infer()),list()))
  52       rhs2=Operation("+",list(Cste(1),Variable("%eps",Infer()),list()))
  53       tree.rhs=Rhs_tlist(tree.rhs(1),rhs2)
  54       tree.name="bdiag"
  55       tree.lhs(1).dims=list(A.dims(1),A.dims(1))
  56       tree.lhs(1).type=Type(Double,Unknown)
  57       tree.lhs(2).dims=list(A.dims(1),A.dims(1))
  58       tree.lhs(2).type=Type(Double,Unknown)
  59     end
  60     return
  61   end
  62
  63   if B.vtype<>Double then
  64     set_infos(gettext("eig() with 2 inputs: consider generalized eigen. Check."),2)
  65   end
  66   m=A.dims(1)
  67   n=A.dims(2)
  68   if lhs==1 then
  69     al=gettempvar(1)
  70     be=gettempvar(2)
  71     insert(Equal(list(al,be),Funcall("spec",1,tree.rhs,list(al,be))))
  72     tree=Operation("./",list(al,be),tree.lhs)
  73
  74     tree.out(1).dims=list(m,1)
  75     tree.out(1).type=Type(Double,Unknown)
  76   else
  77     al=gettempvar(1)
  78     be=gettempvar(2)
  79
  80     insert(Equal(list(al,be,tree.lhs(1)),Funcall("eig",1,tree.rhs,list(al,be,tree.lhs(1)))))
  81
  82     tree=Operation("./",list(al,be),list(tree.lhs(1)))
  83     tree=Funcall("diag",1,list(tree),tree.out)
  84
  85     tree.lhs(1).dims=list(A.dims(1),A.dims(1))
  86     tree.lhs(1).type=Type(Double,Unknown)
  87     tree.lhs(2).dims=list(A.dims(1),A.dims(1))
  88     tree.lhs(2).type=Type(Double,Unknown)
  89   end
  90 // eig(A,B,flag)
  91 else
  92   no_equiv(msprintf(gettext("%s, flag IGNORED."),expression2code(tree)))
  93
  94   tree.rhs(3)=null()
  95
  96   tree.lhs(1).dims=list(A.dims(1),A.dims(1))
  97   tree.lhs(1).type=Type(Double,Unknown)
  98   if lhs==2 then
  99     tree.lhs(2).dims=list(A.dims(1),A.dims(1))
 100     tree.lhs(2).type=Type(Double,Unknown)
 101   end
 102 end
 103
 104 endfunction