Error using tabular/permute and Error in median (line 186)

load dataassign5.mat;

%Input data from TE Chemical Process

X=dataassign5(1:535,1:6); %6 continuous variable

% find dimension of matrix, n=number of rows, p=number of columns/variables

[n,p] = size(X);

ran = min(size(X,1),size(X,2));

if p>ran

p=ran;

end

c= median(X); %median

C=repmat(c,n,1);

d=std(X); %standard deviation

D=repmat(d,n,1);

X=(X-C)./D;

% diagonalisation

[Tmat,E,L] = svd(X,0);

eigmat = E;

% eigenvalues

Efull = diag(E).^2/(n-1);

exp_var = Efull/sum(Efull);

E = Efull(1:p);

exp_var = exp_var(1:p);

for k=1:p

cum_var(k) = sum(exp_var(1:k));

end

%SCREE Plot

figure (01)

bar(exp_var);

title('SCREE Plot')

xlabel('No of PCs');

ylabel('Variance');

% no of principal components

a=20;

% loadings,L and scores,T

L = L(:,1:a);

T = X*L;

% T2 hotelling

I=E';

I=I(1,1:a);

I=diag(I);

I_inv=(I)^(-1/2);

for i=1:n

Tcont(i,:) = (((X(i,:)*L)*I_inv)*L');

Thot(i) = Tcont(i,:)*Tcont(i,:)';

end

% Q residuals

Xmod = T*L';

Err = X - Xmod;

I1=1;

I1(1:p)=I1;

I1=diag(I1);

for i=1:n

Qcont(i,:)= X(i,:)*(I1-L*L');

Qres(i) = Qcont(i,:)*X(i,:)';

end

% T2 limit

lev_conf = 0.99;

F = finv(0.99,a,n-a);

tlim = a*(n - 1)/(n - a)*F;

% Q limit

t1 = sum(E((a+1):end).^1);

t2 = sum(E((a+1):end).^2);

t3 = sum(E((a+1):end).^3);

ho = 1 - (2*t1*t3)/(3*t2^2);

ca = norminv(0.95, 0, 1);

term1 = (ho*ca*(2*t2)^0.5)/t1;

term2 = (t2*ho*(ho - 1))/(t1^2);

qlim = t1*(term1 + 1 + term2)^(1/ho);

%Plot

% read number of samples

M=1:n;

% read T2 critical value

S (1:n)=tlim;

% read Q critical value

N (1:n)=qlim;

%T2 control chart in NOC

figure (02)

plot(M,S,M,Thot);

axis([0,n,0,tlim+20]);

title('T^{2} Control Chart in Normal Operating Condition');

xlabel('Sample No');

ylabel('T^{2} Value');

Thresholdt2= tlim;

%False alarm rate T2

for i=1:n

b(i)=Thot(i)>tlim;

end

fat2=sum(b); %total false alarms

FARt2=fat2/n*100;

%SPE control chart in NOC

figure (03)

plot(M,N,M,Qres);

axis([0,n,0,qlim+5]);

title('SPE Control Chart in Normal Operating Condition');

xlabel('Sample No');

ylabel('SPE Value');

Thresholdq= qlim;

%False alarm rate SPE

for i=1:n

b1(i)=Qres(i)>qlim;

end

faspe=sum(b1); %total false alarms

FARspe=faspe/n*100;

Answer 1

[Christine Tobler]

Applying median to a table directly is not supported.

Either apply median to a specific variable of the table

>> t = table([3; 4; 5], [2; 4; 1])
t =
  3×2 table
    Var1    Var2
    ____    ____
     3       2  
     4       4  
     5       1  

>> median(t.Var1)
ans =
     4

or use varfun to apply the same function to all variables in the table.

>> varfun(@median, t)
ans =
  1×2 table
    median_Var1    median_Var2
    ___________    ___________
         4              2