Add 1;
as the first line of the file:
1;
function fibo = recfibo(n)
if ( n < 2 )
fibo = n;
else
fibo = recfibo(n-1) + recfibo(n-2);
endif
endfunction
disp(recfibo(5))
Any M-file that starts with a function definition is a function M-file, not a script M-file. By adding a meaningless statement to the top, you turn it into a script.
In MATLAB (since fairly recently), a script M-file can define functions at the end of the script. There you’d put the disp
line at the top of the file, and have the function
block at the end, without any script lines after it. However, Octave requires functions to be defined before you use them, hence it has to come before the script line that uses the function. Octave allowed the definition of functions within a script file before MATLAB introduced that feature, hence their implementation is not compatible with that of MATLAB.