Error using fprintf. Invalid format

This is my code for a function that takes two files and combines parts of these files into one new file.

function []=CreateNewMarkersEEGlab(pNumber)
dataFileName=strcat(int2str(pNumber),'_logfile.txt');
fid = fopen(dataFileName);
C = textscan(fid, '%s%s%s%s%s%s%s%s%s%s%s%s%s%s', 'headerlines', 1);
rScore=C{12}; 
sNumber=C{5};
cNumber=C{6};
subNumber=C{7};
tcode=C{10}; 
fclose(fid);

% compute the new marker
for i=1:156
    if rScore{i}=='1'
        respMarker='corrresp';
    else
        respMarker='incorrresp';
    end
    if tcode{i}=='1'
        corrMarker='corr';
    else 
        corrMarker='incorr';
    end    
        newMarker(i)= strcat('S1_con',cNumber(i),'_sub',subNumber(i),'_',corrMarker,'_',respMarker,'_SNr',sNumber(i));  
end

% read the old marker file
dataFileName=strcat('EEG_Anne_',int2str(pNumber),'.vmrk');
fid = fopen(dataFileName);
headline1=fgets(fid);
headline2=fgets(fid);
headline3=fgets(fid);
headline4=fgets(fid);
headline5=fgets(fid);
headline6=fgets(fid);
headline7=fgets(fid);
headline8=fgets(fid);
headline9=fgets(fid);
headline10=fgets(fid);
headline11=fgets(fid);
headline12=fgets(fid);
headline13=fgets(fid);
C = textscan(fid, '%s%s%d%d%d','Delimiter',',');
Type=C{1};
Position=C{3};
Length=C{4};
Channel=C{5};
fclose(fid);

% rewrite the new marker file
outFileName=strcat('EEG_Anne_',int2str(pNumber),'_new.vmrk');
fid = fopen(outFileName,'w+');
fprintf(fid,headline1);
fprintf(fid,headline2);
fprintf(fid,headline3);
fprintf(fid,headline4);
fprintf(fid,headline5);
fprintf(fid,headline6);
fprintf(fid,headline7);
fprintf(fid,headline8);
fprintf(fid,headline9);
fprintf(fid,headline10);
fprintf(fid,headline11);
fprintf(fid,headline12);
fprintf(fid,headline13);
for i=1:156
    temp=[Type(i),',', newMarker(i),',', num2str(Position(i)),',',num2str(Length(i)),',',Channel(i),'\r\n'];
    fprintf(fid,temp);
end
fclose(fid);

The error code I get refers to the second last line and reads this:

Error using fprintf Invalid format.

Error in CreateNewMarkersEEGlab (line 73) fprintf(fid,temp);

What am I doing wrong? Thanks a lot for your help!

Answer 1

[Walter Roberson]

The temp you construct is a cell array, not a string. You cannot pass a cell array as a format.

for i=1:156
  fprintf(fid, '%s,%s,%d,%d,%s\r\n', Type{i}, newMarker{i}, Position(i), Length(i), Channel{i});
end

[Anne Mickan]

Hi Walter, thanks for your help. If I replace my old code with your new one, however, I get a new error message:

Cell contents reference from a non-cell array object. What should I do?

Error in CreateNewMarkersEEGlab (line 72)

fprintf(fid, '%s,%s,%s,%s,%s\r\n', Type{i}, newMarker{i}, Position(i), Length(i), Channel{i});

[Stephen23]

Using the debugger stop your code just before that fprintf and check the class of the variables used in the fprintf statement (i.e. Type, newMarker, Position, and Length). I.e. which are cell arrays, and which are numeric arrays. The simply use {} for the cell array variables, and () for the numeric array variables.

The error messge tis telling you that you are using cell array indexing notation {} with something that is not a cell array. So this is what you need to check for.

I suspect that newMarker might use the wrong kind of brackets, as it is not clear in your code what class of variable it is.

Note that you should avoid using names that differ only in case from inbuilt function names, e.g. Length is very similar to length.

[Walter Roberson]

for i=1:156
  fprintf(fid, '%s,%s,%d,%d,%d\r\n', Type{i}, newMarker{i}, Position(i), Length(i), Channel(i));
end

Note: I recommend that you change how you store newMarker. You currently have

        newMarker(i)= strcat('S1_con',cNumber(i),'_sub',subNumber(i),'_',corrMarker,'_',respMarker,'_SNr',sNumber(i));

and I suggest you change that to

        newMarker{i} = sprintf('S1_con%s_sub%s_%s_%s_Snr_%s',
cNumber{i}, subNumber{i}, corrMarker, respMarker, sNumber{i});

Also, the two places you use == '1' should be changed:

if rScore{i}=='1'

to

if strcmp(rScore{i}, '1')

and likewise a few lines down.

[Anne Mickan]

Thank you very much! That worked!