fopen and fget reading lines from a text

Hi, I try to work with fget and fopen, and I would like to read the first three lines from a text file (attached), and print them on the MATLAB output,

I try

fid = fopen('test.txt');
line_ex = fgetl(5)  % read line excluding newline character
fid = fopen('test.txt');
line_ex = fgetl(5)  % read line excluding newline character
fid = fopen('test.txt');
line_ex = fgetl(5)  % read line excluding newline character

However, this prints out only the three first lines one time, then it continues to 4,5,6, then 7,8,9 etc.

Is there a better way to simply reproduce the three first lines of the text files, with the same command, over again?

Thanks

Answer 1

[Dyuman Joshi]

You need to use the file ID as input to fgetl -

fid = fopen('test.txt');

%lines to read
num = 3;

%Preallocate a cell array to store the data
C = cell(num,1);

for k=1:num
    %Read the line
    str = fgetl(fid);
    %Store it in a cell element
    C{k} = str;
    %Display it
    disp(str)
end

X-412.538 Y-150.417 Z505.02 B21=-24.976 A1=19.761 C0.
X-412.313 Y-151.044 Z505.02 B21=-24.98 A1=19.85 C0.
X-412.087 Y-151.67 Z505.02 B21=-24.984 A1=19.938 C0.

C

C = 3×1 cell array
    {'X-412.538 Y-150.417 Z505.02 B21=-24.976 A1=19.761 C0.'}
    {'X-412.313 Y-151.044 Z505.02 B21=-24.98 A1=19.85 C0.'  }
    {'X-412.087 Y-151.67 Z505.02 B21=-24.984 A1=19.938 C0.' }

[Sergio]

that File ID was given as 5

[Dyuman Joshi]

Okay.

But it's not a good idea to hard code values. Better to store it as a variable and use it accordingly.

[Stephen23]

"that File ID was given as 5"

Do not hard-code the File ID.