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fnedist.gms : Test correctness of edist intrinsic


Norm 2 function

f := sqrt(sqr(x1)+sqr(x2)+...)

g1.. = x1/f  x2/f  ...

hij = -xi*xj/f^3     for i<>j
      (f^2-xi^2)/f^3 for i=j

Small Model of Type: GAMS
$title 'Test correctness of edist intrinsic' (FNEDIST,SEQ=197) $ontext Norm 2 function f := sqrt(sqr(x1)+sqr(x2)+...) g1.. = x1/f x2/f ... hij = -xi*xj/f^3 for i<>j (f^2-xi^2)/f^3 for i=j $offtext Sets arg / n0*n9 / T / p1*p1000 /; alias (arg,argp); Parameters data(arg) testi(*,*) testm(*,*), a, b; loop {T, data(arg) = uniform(-100,100); testi('' ,'' ) = edist.value(data('n0'),data('n1'),data('n2'),data('n3'),data('n4'), data('n5'),data('n6'),data('n7'),data('n8'),data('n9')); loop(arg, testi(arg,'' ) = edist.grad (ord(arg): data('n0'),data('n1'),data('n2'),data('n3'),data('n4'), data('n5'),data('n6'),data('n7'),data('n8'),data('n9'))); loop((arg,argp), testi(arg,argp) = edist.hess (ord(arg):ord(argp): data('n0'),data('n1'),data('n2'),data('n3'),data('n4'), data('n5'),data('n6'),data('n7'),data('n8'),data('n9'))); testm('','') = sqrt(sum(arg, sqr(data(arg)))); a = 1/testm('',''); b = a*a*a; testm(arg,'') = data(arg)*a; testm(arg,argp) = -data(arg)*data(argp)*b; * Since we already calculated hess(xi,xi) with the formula for i<>j we can use: hess(xi,xi) = 1/f + hess(xi,xi) testm(arg,arg) = a + testm(arg,arg); abort$(abs( testi( '', '')-testm( '', '')) >1e-6) 'wrong function value', data, testi, testm; abort$(abs(sum(arg, testi(arg, '')-testm(arg, '')))>1e-6) 'wrong gradient value', data, testi, testm; abort$(abs(sum((arg,argp), testi(arg,argp)-testm(arg,argp)))>1e-6) 'wrong hessian value', data, testi, testm; };