Develop a Matlab code to calculate the numerical differentia
Solution
Following is the required matlab code, equations are numbered in order given in the question:
x = [0,1,2,3,4,5,6,7,8];
 fx =[0.5, 4, 5.1, 9.8, 10.3, 9.4, 8.7, 6.6, 5.4 ];
%Equation numbered according to the given order in question
 %Equation 1
 dfx = zeros(8,1);
 for i=1:8
     dfx(i,1) = fx(i+1) - fx(i);
 end
 figure;
 plot( [0,1,2,3,4,5,6,7,8 ], fx, \'r\', [0,1,2,3,4,5,6,7 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 1\');
%Equation 2
 dfx = zeros(7,1);
 for i=1:7
     dfx(i,1) = (-fx(i+2) + 4*fx(i+1) - 3*fx(i) )/2.0;
 end
 figure;
 plot( [0,1,2,3,4,5,6,7,8 ], fx, \'r\', [0,1,2,3,4,5,6 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 2\');
%Backward Difference
 %Equation 3
 dfx = zeros(8,1);
 for i=2:9
     dfx(i-1,1) = fx(i) - fx(i-1);
 end
 figure;
 plot( [0,1,2,3,4,5,6,7,8 ], fx, \'r\', [ 1,2,3,4,5,6,7,8 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 3\');
%Equation 4
 dfx = zeros(7,1);
 for i=3:9
     dfx(i-2,1) = ( fx(i-2) - 4*fx(i-1) + 3*fx(i) )/2.0;
 end
 figure;
 plot( [ 0,1,2,3,4,5,6,7,8 ], fx, \'r\', [ 2,3,4,5,6,7,8 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 4\');
%Centerd Difference
 %Equation 5
 dfx = zeros(7,1);
 for i=2:8
     dfx(i-1,1) = (fx(i+1) - fx(i-1))/2;
 end
 figure;
 plot( [0,1,2,3,4,5,6,7,8 ], fx, \'r\', [ 1,2,3,4,5,6,7 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 5\');
%Equation 6
 dfx = zeros(5,1);
 for i=3:7
     dfx(i-2,1) = ( -fx(i+2) + 8*fx(i+1) - 8*fx(i-1) + fx(i-2) )/12.0;
 end
 figure;
 plot( [ 0,1,2,3,4,5,6,7,8 ], fx, \'r\', [ 2,3,4,5,6 ], dfx , \'black\' );
 ylabel( \'Amplitude\' );
 xlabel( \'x\' );
 legend(\'f(x)\',\'df(x)\');
 title(\'Equation 6\');


