getf('stepf.sci','n');  /// \sleftarrow{\normalfont load \verb+f1+ with \verb+getf+ option \verb+'n'+}
x=int(10*rand(1,4));  /// \sleftarrow{\normalfont argument of \verb+f1+}
x=90;
exec (f1,7) /// \sleftarrow{\normalfont single-step execution \verb+f1+}