Program calculate RLC circuit

{ RLC-FILE.PAS                           Copyright (c) Jan Benkovic }
{ Program na vypocet RLC obvodov. Vysledok uklada do suboru.        }
{                                                                   }
{ Datum:03.03.2000                             http://www.trsek.com }
 
Program RLC_do_suboru;
uses crt;
var
 f:integer;
 fmin:integer;
 fmax:integer;
 i:integer;
 l:real;
 c:real;
 r:real;
 t:text;
 
function XL(f:integer):real;
 begin
  XL:=2*PI*f*l;
 end;
 
function XC(f:integer):real;
 begin
  XC:=1/(2*PI*f*c);
 end;
 
function Z(f:integer):real;
 begin
  Z:=sqrt(sqr((r)+(XL(f)-XC(f))));
 end;
 
Begin
 clrscr;
 write  ('  Zadaj hodnotu odporu rezistora: ');
 readln (r);
 write  ('Zadaj hodnotu indukcnosti cievky: ');
 readln (l);
 write  ('     Zadaj kapacitu kondenzatora: ');
 readln (c);
 clrscr;
 assign(t,'vypis');
 reset(t);
 rewrite(t);
 writeln(t,'   f             R             XL              XC               Z');
 writeln('   f             R             XL              XC               Z');
 for i:=1 to 20 do
  begin
   f:=i*5;
   writeln (' ',f:3,'         ',R:5:2,'           ',XL(f):8:3,'       ',XC(f):8:3,'         ',Z(f):8:3);
   writeln (t,' ',f:3,'         ',R:5:2,'           ',XL(f):8:3,'       ',XC(f):8:3,'         ',Z(f):8:3);
  end;
 close(t);
 readkey;
end.