How can I put multiple functions in one file and later get access to all of them in the octave interpreter ? I don\'t want to have a thousand files and want to group functio
What you're looking for is called “script files”, defined there: http://www.gnu.org/software/octave/doc/interpreter/Script-Files.html
Once you have saved all your function definitions in a single script file, use source("filename") to have access to these functions within the interpreter.