Add another column to the right end of this array

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This a code within the book of Cengels' Differential Equations. I would like to add a column with the value exact (1.5) at the right side at the end of the array.
lower=0;upper=1;
m=1;
exact=1.5;
f=@(x)7*x-6*x^2;
for nstrip=[1,2,3,4,5,10:10:50,100,200]
h=(upper-lower)/nstrip;
x=lower;value=0;
for n=1:nstrip
value=value+h*(f(x)+f(x+h))/2;
x=x+h;
error(m,:)=[nstrip,value,100*abs(value-exact)/exact];
end
m=m+1;
end
error
This is what I obtain:
I would like to obtain this
thanks for your help

Answers (1)

James Tursa
James Tursa on 29 Mar 2023
your_matrix(:,end+1) = 1.5;
  4 Comments
Torsten
Torsten on 29 Mar 2023
Edited: Torsten on 29 Mar 2023
lower=0;upper=1;
m=1;
exact=1.5;
f=@(x)7*x-6*x^2;
Nstrip=[1,2,3,4,5,10:10:50,100,200];
my_results = zeros(numel(Nstrip),4);
for nstrip=Nstrip
h=(upper-lower)/nstrip;
x=lower;value=0;
for n=1:nstrip
value=value+h*(f(x)+f(x+h))/2;
x=x+h;
end
my_results(m,:) = [nstrip,value,100*abs((value-exact)/exact),exact];
m=m+1;
end
my_results
my_results = 12×4
1.0000 0.5000 66.6667 1.5000 2.0000 1.2500 16.6667 1.5000 3.0000 1.3889 7.4074 1.5000 4.0000 1.4375 4.1667 1.5000 5.0000 1.4600 2.6667 1.5000 10.0000 1.4900 0.6667 1.5000 20.0000 1.4975 0.1667 1.5000 30.0000 1.4989 0.0741 1.5000 40.0000 1.4994 0.0417 1.5000 50.0000 1.4996 0.0267 1.5000
Jose Ceballos
Jose Ceballos on 29 Mar 2023
thank you very much for your help.....i appreciate it

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