pdifftest_result.txt

%% Observation and Conclusion:

% Output:
% pdifftest
% For h = w = 0.200:
%  maximum absolute error for derivative w.r.t x is 6.653346e-03
%  maximum absolute error for derivative w.r.t y is 1.110223e-15.
% 
% For h = w = 0.100:
%  maximum absolute error for derivative w.r.t x is 1.665834e-03
%  maximum absolute error for derivative w.r.t y is 2.442491e-15.
% 
% For h = w = 0.050:
%  maximum absolute error for derivative w.r.t x is 4.166146e-04
%  maximum absolute error for derivative w.r.t y is 3.774758e-15.

% Observation & Comments:
% It can be clearly observed that the max error in the estimation for the
% derivative wrt to x decreases as the sampling width decreases while for
% the derivative wrt y the max error actually increases as the sampling width
% decreases. This might possibly be because in the range of x greater than
% pi the linear approxmation for the sin function in the estimated formulae
% becomes worse and hence the error becomes bigger as the sampling window is
% magnified.