Hi , all there , i have an excel file that i want to split it by special element value in the file to some files . how can i make it possoble with matlab

The initial excel file is composed of 5678 rows and 4 columns. what i want is to split it to some subfiles according to particular principle . for example '0' in a row

how should i do it in matlab ?

THX

Frank

[Jan]

What have you tried so far? Can you import the file already? Then the input is a matrix already and you can omit the "initial excel file" part.

Answer 1

[Mathieu NOE]

hello

try this

I created first a dummy array with some zeros at lines 25 / 75 / 85

so the for loop will split the data with rows going from 1 to 24 then 25 to 74 , 75 to 84 , 85 to end of array (100th row)

each individual array is stored in a separate excel file

hope this helps

%% 1/ create some dummy data and store in a excel file 
A = rand(100,5);
A(:,1) = (1:100)';

% create some specific (0) values
target_val = 0;
A(25,3) = target_val;
A(75,2) = target_val;
A(85,5) = target_val;

writematrix(A,"dummy.xlsx");

%% 2/ main code
B = readmatrix("dummy.xlsx");
[m,n] = size(B);

tol = 1e-6; % define tolerance
[r,c] = find(abs(B-target_val)<tol);

r = sort(r); % sort r in ascending order

rr = [1;r;m+1];

for ci = 1:numel(rr)-1
    start_row = rr(ci)
    stop_row = rr(ci+1)-1
    data = B(start_row:stop_row,:); % extract rows 
    filename_out = ['out' num2str(ci) '.xlsx'];
    writematrix(data,filename_out);
end
    
    

[Mathieu NOE]

hello

problem solved ?

Answer 2

[Star Strider]

To begin a new sub-array whenever a zero appears in any row, this works —

M = randi([0 20], 15, 4)

M = 15×4

0 3 5 8 7 7 0 2 15 17 3 6 1 9 18 9 7 8 4 16 7 8 0 10 20 11 16 7 11 0 7 14 0 7 13 0 20 14 14 5

ZeroInRow = any(M==0,2);                            % Returns 'true' For Any Row With A '0'
Idx = cumsum(ZeroInRow);                            % Define Grouped Rows By Cumulative Sum
[Lb,Ub] = bounds(Idx);                              % Number Of Instances Of Rows With '0'
StartIdx = Lb;
for k = Lb:Ub
    cidx = k-StartIdx+1;
    C{cidx,:} = M(Idx==k,:);                         % Create Cell Array Of Submatrices Matching Condition
end
C

C = 5×1 cell array
    {[  0 3 5 8]}
    {4×4 double }
    {2×4 double }
    {[11 0 7 14]}
    {7×4 double }

.