function perpAndCoinc() {
  var sys = [];
  var ID = 0;
  var l1 = {
    p1 : {
      x : new TCAD.parametric.Param(ID++, 10),
      y : new TCAD.parametric.Param(ID++, 10)
    },
    p2 : {
      x : new TCAD.parametric.Param(ID++, 300),
      y : new TCAD.parametric.Param(ID++, 300)
    }
  };
  
  
  var l2 = {
    p1 : {
      x : new TCAD.parametric.Param(ID++, 10 + 100),
      y : new TCAD.parametric.Param(ID++, -10 + 100)
    },
    p2 : {
      x : new TCAD.parametric.Param(ID++, 300 + 100),
      y : new TCAD.parametric.Param(ID++, -300 + 100)
    }
  };
  
  
  sys.push(new TCAD.constraints.Perpendicular([l1.p1.x, l1.p1.y, l1.p2.x, l1.p2.y, l2.p1.x, l2.p1.y, l2.p2.x, l2.p2.y]));
  sys.push(new TCAD.constraints.Equal([l1.p1.x, l2.p1.x]));
  sys.push(new TCAD.constraints.Equal([l1.p1.y, l2.p1.y]));
  
  return sys;
  
}


function testCompare() {
  var bfgs_ = perpAndCoinc();
  var lm_ = perpAndCoinc();
  var tr_ = perpAndCoinc();
  var dl_ = perpAndCoinc();
  
//  var bfgs = TCAD.parametric.solve(bfgs_, [], 0, 1);
  var lm = TCAD.parametric.solve(lm_, [], 0, 0);
//  var tr = TCAD.parametric.solve(tr_, [], 0, 2);
  var dl = TCAD.parametric.solve(dl_, [], 0, 5);
  
//  console.log("bfgs: " + bfgs.errorSquare());
  console.log("lm: " + lm.errorSquare());
//  console.log("trusted region: " + tr.errorSquare());
  console.log("dog leg: " + dl.errorSquare());

}

function lsolve() {
  var n = numeric;
  var A = [[2,3], [1,1]];
  var b = [13,5];
//  var At = n.transpose(A);
//  var A = n.dot(At, A);
//  var b = n.dot(At, b);
//  var res = n.dot(n.dot(At, n.inv(n.dot(A, At)) ), b);
//  var res = optim.cg(A, [100, 100, 0], b, 1e-8, 800);
  
  //var qr = new TCAD.math.QR(A);
  //qr.qTy(b);
  //var res = qr.solve(b);

  var res = n.solve(A, b);
  console.log(res);
}