Solving an iterative procedure with respect to some criteria using MATLAB

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I would like to solve the following iterative algorithm based on the given incomplete matrix A, where `-` refers to the missing entries of A (9 missing entries in total):
A = [...
0.5 0.2 0.6 0.4;...
- 0.5 - - ;...
- - 0.5 - ;...
- - - 0.5];
Now I want to fill in the incomplete matrix A by following an iterative algorithm using a function of two variables f(i,k) = i+k+3 and respecting the following criteria here
; ; and ;
**EMV_h** denotes the subset of missing values **MV** that can be estimated in step h; **UV_h** denotes Unknown Values in step h; **KV_h** denotes Known Values in step h; **KnownValue** denotes the nondiagonal nonzero entries of A. Hik_1, Hik_2, and Hik_3 are already written/defined in the Matlab code (it is fine!): i.e.,
; ; and .
For instance, in this matrix:
MV = {[2,1], [3,1], [4,1], [3,2], [4,2], [2,3], [4,3], [2,4],[3,4]}; KnownValue = {[1,2], [1,3], [1,4]};
when h=1, EMV_1 = {[3,2], [4,2], [2,3], [4,3], [2,4],[3,4]}; And when h=2, EMV_2 = {[2,1], [3,1], [4,1]};
The Algorithm is:
Step 0. EMV_0 = empty set;
Step 1. h=1;
Step 2. while EMV_h ~= empty set {
Step 3. for every (i,k) in EMV_h {
Step 4. f(i,k)
Step 5. }
Step 6. h=h++
Step 7. }
I wrote a MATLAB code as follows and it works correctly when h=1. i.e., when EMV_1 = MV. But I couldn't go further when `h=2,3,4,...` i.e. when `**EMV_h ~= MV**`. My question/challenge is to construct `EMV_h` and manage it in the Matlab code. How can I write the Matlab code for EMV_h, please? . Thanks in advance!
clear;clc
global P1;
global n;
% % Incomplete Matrix
% 0 indicates the missing entry position
A = [...
0.5 0.2 0.6 0.4 ;...
0 0.5 0 0 ;...
0 0 0.5 0 ;...
0 0 0 0.5];
n = size(A,1);
M = A; % to write Missing Values (MV)
P1 = A; % to write the nondiagonal Known (Estimated) Values (EV)
P1(1:n+1:end)=0; % To make the diagonal elements zero
%i.e, to make all P zero except the known entries in the nondiagonal position
P1;
% To write Missing Values
[r,s] = find(~M); % Find indices and values of zero elements of P
MV = num2cell([r,s] ,2); %to write the missing values in array
MV;
% The algorithm
EMV = {}; % Estimated missing value, EMV = empty set
h = 1;
while isempty(EMV)
EMV = MV; % Missing Values
index = 1; % index
% for every (i,k) in EMV
for m = 1:length(EMV)
i = EMV{m}(1); % row of EMV
k = EMV{m}(2); % column of EMV
EMV{index} = f(i,k); % puts value in the position of A(i,k)
index = index+1;
end
EMV; % the value of A(i,k) for any given (i,k), cell array form
EMV = cell2mat(EMV); % values in column form
% To write a complete matrix
for s = 1:length(EMV) % s is another index
% put EMV(s) in the position (i,k);
A(MV{s}(1),MV{s}(2)) = EMV(s);
end
A
% EMVh{h} = {EMV}
% h = h+1;
end
pik = 0
pik = 0
pik = 0
pik = 8
pik = 9
pik = 8
pik = 10
pik = 9
pik = 10
A = 4×4
0.5000 0.2000 0.6000 0.4000 0 0.5000 8.0000 9.0000 0 8.0000 0.5000 10.0000 0 9.0000 10.0000 0.5000
function pik = f(i,k)
global P1;
global n;
% to write the nondiagonal Known values (EV)
[u,v]=find(P1); % Find indices and values of nonzero elements of P (nondiagonal)
KnownValue = num2cell( [u,v] ,2); %to write the Known Values in array
%
% Hik_1 = {j~=i,k| (i,j),(j,k) in KnownValue}
Hik_1=setdiff( intersect(v(u==i),u(v==k)) ,[i,k]);
% Hik_2 = {j~=i,k| (j,k),(j,i) in KnownValue}
Hik_2=setdiff( intersect(u(v==i),u(v==k)) ,[i,k]) ;
% Hik_3 = {j~=i,k| (i,j),(k,j) in KnownValue}
Hik_3=setdiff( intersect(v(u==i),v(u==k)) ,[i,k]) ;
% To calculate pik
if ~isempty(Hik_1)||~isempty(Hik_2)||~isempty(Hik_3)
pik = i+k+3;
else
pik =0;
end
pik
end
The answer I got: when h=1,
A = [...
0.5000 0.2000 0.6000 0.4000;...
0 0.5000 8.0000 9.0000;...
0 8.0000 0.5000 10.0000;...
0 9.0000 10.0000 0.5000];
When h=2, the answer should be the following, but I couldn't manage to run it inside the while loop at once. I obtained this result after I run it two times independently.
A = [...
0.5000 0.2000 0.6000 0.4000
6.0000 0.5000 8.0000 9.0000
7.0000 8.0000 0.5000 10.0000
8.0000 9.0000 10.0000 0.5000];

Accepted Answer

Karthik P.V
Karthik P.V on 15 Dec 2021
Edited: Karthik P.V on 15 Dec 2021
Please try this and confirm
clear;clc
global P1;
global n;
% % Incomplete Matrix
% 0 indicates the missing entry position
A = [...
0.5 0.2 0.6 0.4 ;...
0 0.5 0 0 ;...
0 0 0.5 0 ;...
0 0 0 0.5];
for j=1:4%Enter count of h <New>
n = size(A,1);
M = A; % to write Missing Values (MV)
P1 = A; % to write the nondiagonal Known (Estimated) Values (EV)
P1(1:n+1:end)=0; % To make the diagonal elements zero
%i.e, to make all P zero except the known entries in the nondiagonal position
P1;
% To write Missing Values
[r,s] = find(~M); % Find indices and values of zero elements of P
MV = num2cell([r,s] ,2); %to write the missing values in array
MV;
% The algorithm
EMV = {}; % Estimated missing value, EMV = empty set
h = j; % <New>
if isempty(EMV) && ~isempty(MV) % <Mod>
EMV = MV; % Missing Values
index = 1; % index
% for every (i,k) in EMV
for m = 1:length(EMV)
i = EMV{m}(1); % row of EMV
k = EMV{m}(2); % column of EMV
EMV{index} = f(i,k); % puts value in the position of A(i,k)
index = index+1;
end
EMV; % the value of A(i,k) for any given (i,k), cell array form
EMV = cell2mat(EMV); % values in column form
% To write a complete matrix
for s = 1:length(EMV) % s is another index
% put EMV(s) in the position (i,k);
A(MV{s}(1),MV{s}(2)) = EMV(s);
end
A
% EMVh{h} = {EMV}
% h = h+1;
end
% EMV = {};
end
function pik = f(i,k)
global P1;
global n;
% to write the nondiagonal Known values (EV)
[u,v]=find(P1); % Find indices and values of nonzero elements of P (nondiagonal)
KnownValue = num2cell( [u,v] ,2); %to write the Known Values in array
%
% Hik_1 = {j~=i,k| (i,j),(j,k) in KnownValue}
Hik_1=setdiff( intersect(v(u==i),u(v==k)) ,[i,k]);
% Hik_2 = {j~=i,k| (j,k),(j,i) in KnownValue}
Hik_2=setdiff( intersect(u(v==i),u(v==k)) ,[i,k]) ;
% Hik_3 = {j~=i,k| (i,j),(k,j) in KnownValue}
Hik_3=setdiff( intersect(v(u==i),v(u==k)) ,[i,k]) ;
% To calculate pik
if ~isempty(Hik_1)||~isempty(Hik_2)||~isempty(Hik_3)
pik = i+k+3;
else
pik =0;
end
pik
end
  3 Comments
Karthik P.V
Karthik P.V on 16 Dec 2021
clear;clc
global P1;
global n;
% % Incomplete Matrix
% 0 indicates the missing entry position
A = [...
0.5 0.2 0.6 0.4 ;...
0 0.5 0 0 ;...
0 0 0.5 0 ;...
0 0 0 0.5];
h=0;
EMV=[];
MV=0;
while (isempty(EMV) && ~isempty(MV))%for j=1:2%Enter count of h <New>
n = size(A,1);
M = A; % to write Missing Values (MV)
P1 = A; % to write the nondiagonal Known (Estimated) Values (EV)
P1(1:n+1:end)=0; % To make the diagonal elements zero
%i.e, to make all P zero except the known entries in the nondiagonal position
P1;
% To write Missing Values
[r,s] = find(~M); % Find indices and values of zero elements of P
MV = num2cell([r,s] ,2); %to write the missing values in array
MV;
% The algorithm
EMV = {}; % Estimated missing value, EMV = empty set
% h = j; % <New>
while (isempty(EMV) && ~isempty(MV)) % <Mod>
EMV = MV; % Missing Values
index = 1; % index
% for every (i,k) in EMV
for m = 1:length(EMV)
i = EMV{m}(1); % row of EMV
k = EMV{m}(2); % column of EMV
EMV{index} = f(i,k); % puts value in the position of A(i,k)
index = index+1;
end
EMV; % the value of A(i,k) for any given (i,k), cell array form
EMV = cell2mat(EMV); % values in column form
% To write a complete matrix
for s = 1:length(EMV) % s is another index
% put EMV(s) in the position (i,k);
A(MV{s}(1),MV{s}(2)) = EMV(s);
end
A
% EMVh{h} = {EMV}
h = h+1;
end
EMV = {};
end
function pik = f(i,k)
global P1;
global n;
% to write the nondiagonal Known values (EV)
[u,v]=find(P1); % Find indices and values of nonzero elements of P (nondiagonal)
KnownValue = num2cell( [u,v] ,2); %to write the Known Values in array
%
% Hik_1 = {j~=i,k| (i,j),(j,k) in KnownValue}
Hik_1=setdiff( intersect(v(u==i),u(v==k)) ,[i,k]);
% Hik_2 = {j~=i,k| (j,k),(j,i) in KnownValue}
Hik_2=setdiff( intersect(u(v==i),u(v==k)) ,[i,k]) ;
% Hik_3 = {j~=i,k| (i,j),(k,j) in KnownValue}
Hik_3=setdiff( intersect(v(u==i),v(u==k)) ,[i,k]) ;
% To calculate pik
if ~isempty(Hik_1)||~isempty(Hik_2)||~isempty(Hik_3)
pik = i+k+3;
else
pik =0;
end
pik
end
Can you try this?
Note: I have not captured the algorithm changes here

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