array indices must be positive intergers or logical values - not sure why i am getting this error message. same code worked for a friend of mine.
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
John McCann
am 3 Feb. 2021
Beantwortet: Steven Lord
am 3 Feb. 2021
clf reset
x=0:0.1:1;
y=[0.9,6.9,31.6,21.5,34.4,68.2,66.4,114.9,155.9,199.3,209.6];
p1=polyfit(x,y,1);
% the code below calculates the r2 values. You can just copy and paste this
% code after your polyfit to find r2 (as long as you use x,y and p1)
% The polyval function evaluates the equation of the fit at the values of x.
yhat_1=polyval(p1,x);
% coefficient of determination
r2=(sum((y-mean(y)).^2)-sum((y-yhat_1).^2))/sum((y-mean(y)).^2);
fprintf('fit y=%.2fx%+.2f \nR2=%.2f\n', p1(1), p1(2),r2);
4 Kommentare
Akzeptierte Antwort
KSSV
am 3 Feb. 2021
Read about clear. When you feel you are done with your previous code, then you can clear all your workspace variables and then run the fresh code. It looks there might be a variable conflict earlier when there was error.
0 Kommentare
Weitere Antworten (1)
Steven Lord
am 3 Feb. 2021
My guess is that earlier in that code you created variables named sum and/or mean. Attempts to call sum and/or mean while variables named sum and/or mean exist generally will not work, they will be interpreted as attempts to index into the variable.
0 Kommentare
Siehe auch
Kategorien
Mehr zu Loops and Conditional Statements finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!