MATLAB: Can someone please help me know what’s wrong with the code? because it doesn’t show the right graph !

deflection

that's what i have done on Matlab, but I can't get the right graph for the question.
first I created a function :
function [y]=discontinuity(x,a,n,c)
s=length(a);
y=zeros(s,1);
for i=1:s
if x(i)>=a
y(i)=((x(i)-a)^n)/c;
else
y(i)=0;
end
end
end
Then, I created a script
x=0:0.5:360;
y=zeros(length(x),1);
for i=1:length(x)
  y(i)= -((100/24)*x(i))^4+(8500/6)*x(i)^3-27.30e6*x(i)+(100/24)*discontinuity(x(i),120,4,29e6*110)-(2000/6)*discontinuity(x(i),180,3,29e6*110)+(9500/6)*discontinuity(x(i),240,3,29e6*110)-(4000/6)*discontinuity(x(i),300,3,29e6*110);
end
plot(x,y)
grid on
xlabel('distance in inches')
ylabel('deflection in inches')

Best Answer

This function:
function y = discontinuity(x,a,n)
y = max(0,x-a).^n;
end
and this script:
x = 0:0.5:360;
y = 1/(29e6 * 110) * (...
  - (100/24)*x.^4 + (8500/6)*x.^3 - 27.30e6*x...
  + (100/24)*discontinuity(x,120,4)...
  - (2000/6)*discontinuity(x,180,3)...
  + (9500/6)*discontinuity(x,240,3)...
  - (4000/6)*discontinuity(x,300,3));
plot(x,y)
grid on
xlabel('distance in inches')
ylabel('deflection in inches')
gives:
MATLAB is a beautiful high-level language. Don't make it slow and ugly by trying to solve every task using loops, as if it were some low-level language like C:
https://www.mathworks.com/help/matlab/matlab_prog/vectorization.html
https://www.mathworks.com/matlabcentral/answers/228557-experts-of-matlab-how-did-you-learn-any-advice-for-beginner-intermediate-users
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