![](bg5.png)
ual measure on the problem operator form compared
to the orthogonal collocation and tau methods.
The orthogonal collocation method is favorable
considering the simplicity of implementation com-
pared to the tau and leas-squares methods. Moreover,
the orthogonal collocation method uses less computa-
tional costs per iteration than the relatively more com-
putational demanding tau and least-squares methods.
5 CONCLUSIONS
The accuracy of the orthogonal collocation, tau and
least-squares method can be evaluated on different
residual measure definitions. Dependent on the resid-
ual measure definition adopted, the relatively perfor-
mance of the numerical methods may change signifi-
cantly. However, the simulation results of the present
PB problem indicate that the orthogonal collocation
and tau method are favorable above the least-squares
method considering accuracy. Nevertheless, the or-
thogonal collocation method uses less computational
costs per iteration than the tau and least-squares meth-
ods. Furthermore, the orthogonal collocation method
holds the simplest algebraic theory, and is thus asso-
ciated with the simplest implementation issues.
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