Real / integer?

[turbomen]

Dear Sir,

I have got confused to the real / integer. Would you mind helping to express it to me?

I have got the answer of the following question:

Write a menu system for the currency exchange program. My menu could look like this:

Exchange rates
How much money would you like to exchange?

Press 1 for Australian dollars
2 for US dollars
3 for English pounds
4 for Japanese yen
5 for Euros
6 for Indian rupees
7 for PNG kina
8 for SA rand

My answer:

program Conversion_with_menuII;

{$APPTYPE CONSOLE}

uses
  SysUtils;

const
  aus=0.9024;
  us=0.7697;
  eng=0.3803;
  y=0.9144;
  e=0.5657;
  rup=31.17;
  kina=1.6197;
  rand=5.1805;

var
  nz_dollar: real;
  aus_out: real;
  us_out: real;
  eng_out: real;
  y_out: real;
  e_out: real;
  rup_out: real;
  kina_out: real;
  rand_out: real;
  choice: integer;

begin
  write('How much money would you lie to change? :$');
  readln(nz_dollar);
  writeln('Please select which currency you would like to convert to');
  writeln('Press 1 for Australian dollars');
  writeln('Press 2 for US dollars');
  writeln('Press 3 for English pounds');
  writeln('Press 4 for Japanese yen');
  writeln('Press 5 for Euros');
  writeln('Press 6 for Indian rupees');
  writeln('Press 7 for PNG kina');
  writeln('Press 8 for SA rand');
  readln(choice);
case choice of
  1: begin
  aus_out:=nz_dollar*aus;
  writeln('The amount in Australian Dollars is: $',aus_out:6:2);
  end;
  2: begin
  us_out:=nz_dollar*us;
  writeln('The amount in US dollars is: $',us_out:6:2);
  end;
  3: begin
  eng_out:=nz_dollar*eng;
  writeln('The amount in English pounds is: $',eng_out:6:2);
  end;
  4: begin
  y_out:=nz_dollar*y;
  writeln('The amount in Japanese yen is: $',y_out:6:2);
  end;
  5: begin
  e_out:=nz_dollar*e;
  writeln('The amount in Euros is: $',e_out:6:2);
  end;
  6: begin
  rup_out:=nz_dollar*rup;
  writeln('The amount in Indian rupees is $',rup_out:6:2);
  end;
  7: begin
  kina_out:=nz_dollar*kina;
  writeln('The amount in PNG kina is $',kina_out:6:2);
  end;
  8: begin
  rand_out:=nz_dollar*rand;
  writeln('The amount in SA rand is $',rand_out:6:2);
  end;
  end;
  readln;
end.

I have tried to change the real to integer but it is work. Could you express the reason to me please?

Cheers,

[FlamingClaw]

What do you want convert real to integer?

[FlamingClaw]

if only so
writeln('The amount in SA rand is $',rand_out:1:0);
and the result seems like integer number like 12 or 34 without decimal point.....
:D

[FlamingClaw]

Int will give you the number before the comma in a real number.

program Convert;

var
r: Real;

begin
r := Int(3.14);
end.

Frac will give you the number after the comma in a real number.

program Convert;

var
r: Real;

begin
r := Frac(3.14);
end.

Round will round off a real number to the nearest integer.

program Convert;

var
i: Integer;

begin
i := Round(3.14);
end.

Trunc will give you the number before the comma of a real number as an integer.

program Convert;

var
i: Integer;

begin
i := Trunc(3.14);
end.

enough? :D

[turbomen]

Dear Sir,

Thank you for detailed expression.

Cheers,