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Is my coding assignment correct?

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Eduardo Gallegos
Eduardo Gallegos on 30 Nov 2022
Commented: Dyuman Joshi on 30 Nov 2022
Hi all, I've been working on this assignment for a few hours & searching for the right way to code this but I'm still unsure if it is correct. Can someone please let me know if this is correct. I'm mostly unsure about 4 and 5.
Instructions.
1. [1 pt] Generate this set of linear data:
x0 = 1:1:20;
y0 = -5 +2*x0;
2a. [1 pt] Add measurement to the y values:
y1 = y0 + 1.0*randn(size(y0));
2b. (1 pt) Open a new figure and plot the noisy data with black circle markers:
3. [3 pts] Use polyfit( ) to fit a line to the noisy data.
4. [3 pts] Use polyval( ) to compute the y-values of the fitted line, using x0 for the x-values.
5. [1 pt] Plot the fitted line on the same figure as the noisy data. Use a red dashed line: 'r--'
My code.
x0 = 1:1:20;
y0 = -5 +2*x0;
y1 = y0 + 1.0*randn(size(y0));
figure;
plot(x0,y1,'o','MarkerFaceColor','k')
grid on;
hold on;
coeffs2 = polyfit(x0,y1,1);
besty = coeffs2(1)*x0 + coeffs2(2);
plot(x0,y1,'o',x0,besty)
x2 = linspace(0,2);
y2 = polyval(coeffs2,x2)
plot(x2,y2,'r--')
  1 Comment
Dyuman Joshi
Dyuman Joshi on 30 Nov 2022
It looks good, but there's a bit of redundant code
%Task 1
x0 = 1:1:20;
y0 = -5 +2*x0;
%Task 2a
y1 = y0 + 1.0*randn(size(y0));
%Task 2b
figure;
plot(x0,y1,'k.','MarkerSize',10)
grid on;
hold on;
%Task 3
coeffs2 = polyfit(x0,y1,1);
%Task 4
y2 = polyval(coeffs2,x0);
%Task 5
plot(x0,y2,'r--')

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