convert xlsread code to use a cell array

I have a code that compares the cells of an excel sheet to incoming data over serial. The incoming string looks like this:

Reader1:  0071803F6AA40%

the code takes the number after the reader, and uses that to tell which row the proper tag is located (1 is A, 2 is B, etc). it then compares the tag, and if they are the same, the coide turns a gui panel green. if they are duifferent, the gui panel turns red. here is the code"

handles.uipanels = [handles.uipanel1, handles.uipanel2, handles.uipanel3, handles.uipanel4, handles.uipanel5, handles.uipanel6, handles.uipanel7, handles.uipanel8];
portlist = {'COM3'}; % , 'COM4', 'COM5', 'COM6'
nport = length(portlist);
tags = cell(1, nport);
cleanups = cell(1, nport);
for portidx = 1 : nport
    delete(instrfind('Port', portlist{portidx})); % removes possibility for 'Port not available' error
    tags{portidx} = serial(portlist{portidx}); %initializes the port to be used
    fopen(tags{portidx}); %opens th eport
    cleanups{portidx} = onCleanup(@() fclose(portlist{portidx}));
end

BOX = char(zeros(8,14)); % matrix to be populated with incoming serial data
TrueValueData = 'C:\Users\Administrator\Dropbox (*********)\********** Team Folder\Matlab\RFID chip reader\RfidChipData\RfidChipTrueValues.xlsx';
% location of stored master tags  
[~,~,TrueValMat] = xlsread(TrueValueData); % reads our excel file into the proper format
% Creates matrix filled with the correct values
% indexed by box, which is the first row
% all proceeding rows are the master value
for i=1:inf
  pause(0.01)
  %     for n = 1:2
  for portidx = 1 : nport
    nbase = portidx * 2 - 1;
    for n = nbase:nbase+1
      if i>10 % positive reading
        %             readData = fscanf(tag);
        readData = fscanf(tags{portidx});
        if length(readData)>12
          BOX(str2double(readData(8)),1:14)= readData(11:24);
          if strcmp(TrueValMat{2,n}, BOX(n,:)) %cannot sub-index to CELL types normally, must use this method
            set(handles.uipanels(n), 'BackgroundColor', 'g');
          else
            set(handles.uipanels(n), 'BackgroundColor', 'r');
          end
          drawnow
                    

instead of TrueValMat coming from an xlsread(), I want it to come from a string array. How would I get the rest of the code to function with this change?

[dpb]

What seems to be the problem if you simply reference the string array w/ regular parens instead of the curlies?

[Walter Roberson]

You can use {} with a string array too: it extracts the underlying character vector.

[avram alter]

dpb: when I drop the braces for () I get an index size error. I think I that's to do with the

BOX(8, 14);

But I am not sure.

Walter: I got the error that brace indexing is not supported for variables of that type.

[Walter Roberson]

Brace indexing is supported for string arrays, and always has been since string arrays were introduced in R2016b.

>> R = string(randi(9,20,20))

R = 

  20×20 string array

    "6"    "6"    "6"    "4"    "7"    "6"    "9"    "3"    "8"    "3"    "6"    "5"    "2"    "3"    "6"    "4"    "6"    "6"    "7"    "8"
    "2"    "5"    "7"    "8"    "9"    "2"    "5"    "4"    "6"    "7"    "8"    "8"    "9"    "7"    "8"    "3"    "1"    "5"    "9"    "5"
    "6"    "9"    "3"    "2"    "9"    "8"    "9"    "5"    "4"    "2"    "3"    "3"    "1"    "4"    "9"    "4"    "5"    "9"    "7"    "8"
    "7"    "4"    "6"    "4"    "2"    "7"    "3"    "7"    "8"    "5"    "5"    "5"    "9"    "2"    "4"    "2"    "2"    "3"    "6"    "4"
    "1"    "6"    "4"    "9"    "9"    "3"    "6"    "7"    "1"    "2"    "9"    "1"    "9"    "1"    "7"    "5"    "6"    "8"    "9"    "8"
    "1"    "9"    "7"    "8"    "3"    "9"    "4"    "1"    "5"    "4"    "7"    "1"    "6"    "8"    "1"    "6"    "7"    "2"    "8"    "8"
    "1"    "4"    "5"    "2"    "2"    "1"    "1"    "4"    "7"    "5"    "6"    "1"    "9"    "4"    "7"    "2"    "4"    "2"    "6"    "3"
    "6"    "8"    "2"    "6"    "1"    "1"    "1"    "5"    "8"    "9"    "3"    "1"    "2"    "5"    "7"    "2"    "6"    "8"    "7"    "4"
    "9"    "3"    "2"    "5"    "8"    "2"    "6"    "3"    "5"    "2"    "5"    "9"    "9"    "6"    "1"    "7"    "3"    "9"    "3"    "4"
    "5"    "5"    "8"    "6"    "2"    "5"    "8"    "5"    "6"    "1"    "6"    "9"    "1"    "1"    "1"    "9"    "7"    "6"    "4"    "8"
    "7"    "5"    "3"    "7"    "1"    "2"    "2"    "4"    "4"    "8"    "8"    "1"    "1"    "7"    "6"    "1"    "1"    "1"    "1"    "8"
    "8"    "2"    "2"    "5"    "9"    "3"    "4"    "3"    "9"    "7"    "2"    "7"    "4"    "9"    "1"    "8"    "1"    "5"    "3"    "4"
    "7"    "6"    "9"    "8"    "7"    "8"    "2"    "9"    "7"    "6"    "8"    "1"    "8"    "4"    "8"    "8"    "8"    "5"    "9"    "2"
    "7"    "5"    "1"    "3"    "1"    "9"    "1"    "1"    "7"    "1"    "2"    "5"    "2"    "7"    "3"    "8"    "2"    "2"    "1"    "9"
    "9"    "8"    "9"    "8"    "6"    "2"    "9"    "5"    "9"    "4"    "1"    "9"    "7"    "5"    "7"    "9"    "9"    "1"    "5"    "7"
    "8"    "7"    "9"    "4"    "6"    "3"    "4"    "5"    "2"    "4"    "8"    "2"    "8"    "9"    "3"    "8"    "1"    "5"    "9"    "3"
    "8"    "1"    "6"    "1"    "5"    "5"    "2"    "7"    "5"    "4"    "6"    "8"    "9"    "5"    "6"    "1"    "3"    "5"    "3"    "6"
    "8"    "4"    "8"    "5"    "3"    "7"    "5"    "5"    "8"    "2"    "4"    "4"    "6"    "4"    "7"    "6"    "2"    "7"    "6"    "2"
    "8"    "3"    "6"    "5"    "5"    "2"    "5"    "6"    "9"    "3"    "2"    "6"    "9"    "8"    "2"    "8"    "1"    "3"    "5"    "4"
    "9"    "4"    "6"    "8"    "7"    "9"    "1"    "1"    "8"    "7"    "1"    "3"    "4"    "5"    "8"    "6"    "6"    "1"    "9"    "6"

>> R{8,14}

ans =

    '5'

[avram alter]

The way I built my array is surrounded by braces.

C = {'0000478h4dj', '4502jn9u3mr84', '000274u5ll3y'};

This is a stupid question, but that changes things, right?

[Walter Roberson]

That is not a string array, that is a cell array of character vectors. And it does support {} indexing:

>> C = {'0000478h4dj', '4502jn9u3mr84', '000274u5ll3y'};
>> C{1,2}

ans =

    '4502jn9u3mr84'