Get "The expression to the left of the equals sign is not a valid target for an assignment" Error Message for Every Single Assignment

I'm working to adapt an old version of code to new data so that I can have a more streamlined method of analyzing the data I get from a plate reader.

I'm currently going through my old code from top to bottom and editing and troubleshooting as I go.

For some reason I am getting the error message "The expression to the left of the equals sign is not a valid target for an assignment"on every assignment (example line 17 and 18).

I'm not new to MatLab but I must be missing something obvious because I've never had issues before.

Below is my code (not I've only edits to like 18 so the following lines might have variables I don't use etc.) You'll also notice I call another fuction in the code so I've addde that function's code below my actual function code in case it's helpful for troubleshooting.

function GeneralAnalysis
%For 96 well or 384 well plates

%need to enter file name as string in purple
filename='MTT Calibration';
newfilename= strcat(filename,' formatted');
dataname = '3-10'; % User input
%Read data
[data,words]=xlsread(filename);

FileName,NumConditions,WellsDescription,WellConditions,BackgroundWells,FileName = ImportDataDescription(dataname)

% First plot everything to look for contamination/outliers
% Plot blanks
blankwells = ['F2','F3','F4','F5','F6','F7','F8','F9','F10';
b = find(strcmp(blankwells,wellnames),1);
wellnames={'Time','',wellnames{:}};
tpn=0; %Initialize: number of time points in data set
rows=0; %Initialize: rows on plate
empty=0; %Keeps track of once you've gone thorugh all the rows once
idx = find(ismember(words, 'Plate:')); % Find where the data starts
time = exractNonNaNArray(data(idx+3:end,1));
formatteddata=zeros(length(time)+1,98);

time=time*60*24;
formatteddata(2:end,1)=time;
for t=1:length(time)
    formatteddata(t+1,1) = time(t);
    for row=1:8
        for col=1:12
         formatteddata(t+1,col+2+(row*10-10)) = data(((idx+2)+(t*9)-(10-row)),2+col);
        end
    end
end

% Convert wellnames from a cell array to an array of strings

wellnames=string(wellnames);

fid = fopen(strcat(newfilename,'.csv'),'w');
fprintf(fid,'%s,',wellnames');
fprintf(fid,[repmat('%f,', 1, size(formatteddata, 2)) '\n'],formatteddata');
fclose(fid);

end

function FileName,NumConditions,WellsDescription,WellConditions,BackgroundWells,FileName = ImportDataDescription(dataname)
%%Import information about each run using formated Excel sheet
[~,~,AllDataDescriptions] = xlsread ('DataDescriptions.xls'); % Imported by cell, so strings are cell strings use {} not []
% Find file name
[~, DataCol] = find(strcmp(dataname,AllDataDescriptions),1); % Returns a matrix where the first column is the row and the second column is the corresponding column
% Imports all formatted information
NumConditions = AllDataDescriptions{2,DataCol}; % Number of types of wells
BackgroundWells = strsplit(AllDataDescriptions{3,DataCol},','); % 1xN matrix listing the wells that are Background
WellConditions = strsplit(AllDataDescriptions{4,DataCol},';'); %1xN Matrix containg the list of wells with different types
FileName = AllDataDescriptions{1,DataCol};
% loop to sperate types of wells so each row is a different type and the
% columns after 1 are the wells
for i = 1:length(NumConditions)
    WellsDescription(i,:) = strsplit(WellConditions{i},',');
end
end

Thank you in advance for any help!

[Jan]

Please do not let us guess, which lines are the 17th and 18th, when you have this important information already.

Answer 1

[Jan]

The line 15 (perhaps) contains an error already:

blankwells = ['F2','F3','F4','F5','F6','F7','F8','F9','F10';

The closing square bracket is missing. Fix this at first an then find out, if the other errors remain.

Please note, that this line produces the same as:

blankwells = 'F2F3F4F5F6F7F8F9F10';

I doubt whether this is useful. Depending on what wellnames is, you might want a cell string perhaps:

blankwells = {'F2', 'F3', 'F4', 'F5', 'F6', 'F7', 'F8', 'F9', 'F10'};

This line is not valid also:

FileName,NumConditions,WellsDescription,WellConditions,BackgroundWells,FileName = ImportDataDescription(dataname)

Better:

[FileName, NumConditions, WellsDescription, WellConditions, ...
 BackgroundWells, FileName] = ImportDataDescription(dataname);

[Kristen Eller]

Thank you so much. I knew it was something ridiculously silly but I just could not see it myself. It's been a long day but thank you so much for the help on such a small problem