fi;
debug_print(procname,"substitution list",2,_subslist);
#----------------------
# check the solution(s)
#----------------------
if type(solset,list(list)) then #multiple solutions
debug_print(procname,"Verifying the ".(nops(solset))." solutions...",1);
goodsols := [];
for k from 1 to nops(solset) do
tmp := expand(subs(_subslist,eval(eqs,solset[k])));
if not type(tmp,list(0=0)) then
debug_print(procname,"Solution ".k." is invalid!",0,solset[k]);
debug_print(procname,"Solution ".k." substituted into normal eqs",0,eqs);
debug_print(procname,"Throwing out solution ".k,0);
else
goodsols := [op(goodsols),solset[k]];
fi;
od;
solset := goodsols;
if nops(solset)=1 then
solset := op(solset);
fi;
else #single solution
debug_print(procname,"Verifying the solution...",1);
eqs := factor(expand(subs(_subslist,eval(eqs,solset))));
if not type(eqs,list(0=0)) then
debug_print(procname,"Solution substituted into normal eqs",0,eqs);
ERROR("Invalid solution!");
fi;
fi;
if time()-time0 > 10 then
debug_print(procname,"Done!",1);
fi;
solset;
end:
4. Examples
Polynomial of degree 1
We start with simple linear regression to check the program. We set the procedure's "chattiness" to
maximum verbosity. The solution appears as the last bracketed expression.
:=
printlevel
4
(
)
leastsqrs
, , ,
=
y
+
A B t
i
t i [
]
,
A B
leastsqrs[0]: i,t,y,ispoly,chi2
, , ,
,
i t
i
y
i
true
=
i 1
N
(
)
- -
y
i
A B t
i
2
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