# "Index in position 1 is invalid. Array indices must be positive integers or logical values."

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Mustafa Kamal on 7 Feb 2019
Commented: Mustafa Kamal on 8 Feb 2019
I get the entitled error when ever i run the code below
nu=sum((i-(n+1)/2).*Y(i,:)
for the equation and also the same error for
de=sqrt(n^3*(sum(Y(i,:)-mean(Y(i,:)))^.2))
for the equation where first is the numerator and second is the denominator of D, "test for normality was given by D’Agostino"
full code
y1=[51 27 37 42 27 43 41 38 36 26 29]';
y2=[36 20 22 36 18 32 22 21 23 31 20]';
y3=[50 26 41 32 33 43 36 31 27 31 25]';
y4=[35 17 37 34 14 35 25 20 25 32 26]';
y5=[42 27 30 27 29 40 38 16 28 36 25]';
Y=[y1 y2 y3 y4 y5]
Y=sort(Y)
[n p]=size(Y)
nu=sum((i-(n+1)/2).*Y(i,:))
de=sqrt(n^3*(sum(Y(i,:)-mean(Y(i,:)))^.2))
D=nu./de
YY=sqrt(n)*(D-inv(2*sqrt(pi)))/0.02998598
##### 2 CommentsShowHide 1 older comment
Rik on 7 Feb 2019
You didn't define i yourself, so now Matlab treats it as the imaginary unit. I don't have a clue what you're trying to do, but it seems you should read the documentation for the symbolic computation toolbox, or rewrite your expression to a normal Matlab computation.

Preethi on 8 Feb 2019
Initialize variable i with 1, before using it
i=1;
##### 2 CommentsShowHide 1 older comment
Mustafa Kamal on 8 Feb 2019
now i have made some changes in the code however i is giving wrong answer
y1=[47.8,46.4,46.3,45.1,47.6,52.5,51.2,49.8,48.1,45.0,51.2,48.5,52.1,48.2,49.6,50.7,47.2,53.3,46.2,46.3]';
y2=[48.8,47.7,46.8,45.3,48.5,53.2,53,50,50.8,47,51.4,49.2,52.8,48.9,50.4,51.7,47.7,54.6,47.5,47.6]';
y3=[49,47.7,47.8,46.1,48.9,53.3,54.3,50.3,52.3,47.3,51.6,53,53.7,49.3,51.2,52.7,48.4,55.1,48.1,51.3]';
y4=[49.7,48.4,48.5,47.2,49.3,53.7,54.5,52.7,54.4,48.3,51.9,55.5,55,49.8,51.8,53.3,49.5,55.3,48.4,51.8]';
Y=[y1 y2 y3 y4];
Y=sort(Y)
n=length(Y)
T=[];
W=[];
for i=1:n
T=[T; ((i-(n+1)/2).*Y(i,:))]
W=[W; sqrt(n^3*((Y(i,:)-mean(Y)).^2))]
end
nu=sum(T)
de=sum(W)
D=nu./de
YY=sqrt(n).*(D-inv(2*sqrt(pi)))./0.02998598
where are the correct answer for the above question is
D=[.2848 .2841 .2866 .2851]
and
YY=[.4021 .2934 .6730 .4491]