Hi,
You can use textscan while reading specific line from the text file and in this case it’s the 4th line. Since there is some initial whitespaces in the 4th line which will go after reading from textscan I have added a tab character which compensates for same.
The following code may help you achieved the same.
- Reading 4th line and creating the changed version based on userInput1 and userInput2.
- Writing all the lines in a new file with changed 4th line.
userInput1 = 50; % User Input 1
userInput2 = 0.5; % User Input 2
% Original File
fid=fopen('check_nf.txt','r');
linenum = 4;
C = textscan(fid,'%s',1,'delimiter','\n', 'headerlines',linenum-1);
line_4_words = strsplit(string(C{1}));
line_4_words(3) = num2str(userInput1);
line_4_words(4) = num2str(userInput2);
changedLine = sprintf('\t') + join(line_4_words) + newline;
fclose(fid);
count = 1;
fid=fopen('check_nf.txt','r');
% New File
fod=fopen('new_nf.txt','w');
while ~feof(fid)
if count == 4
fprintf(fod,'%s',changedLine);
fgets(fid);
else
fprintf(fod,'%s',fgets(fid));
end
count = count + 1;
end
fclose(fod);
fclose(fid);
