График по точкам из файла. Ошибка The specified file was not found

unit Unit9;
 
interface
 
uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;
 
type
  TForm9 = class(TForm)
  Button1: TButton;
  Label1: TLabel;
 
  procedure Button1Click(Sender: TObject);
 
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form9: TForm9;
 
implementation
 {$R *.dfm}
 
procedure TForm9.Button1Click(Sender: TObject);
var
i,num: Integer;
filehnd: TextFile;
//filename: String;
//temp
h_max,w_max,h_scale,w_scale,MO,DISP:extended;
a,b,d:array of integer;
c:array of extended;
 
begin
    AssignFile (filehnd, '1.res');
    Reset (filehnd);
    Read(filehnd,num);
    SetLength(a,num);
    SetLength(b,num);
    SetLength(c,num);
    SetLength(d,num);
    for i:=0 to num-1 do
    Read(filehnd,d[i]);
    for i:=0 to num-1 do
    Read(filehnd,c[i]);
 
    h_max:=0;
    w_max:=0;
 
    for i:=0 to num-1 do
    begin
    if c[i]>h_max then h_max:=c[i];
    if d[i]>w_max then w_max:=d[i];
    end;
 
    h_scale:=(Form9.Height-50)/h_max;
    w_scale:=(Form9.Width-50)/w_max;
 
    for i:=0 to num-1 do
    begin
    b[i]:=Round(c[i]*h_scale)+150;
    a[i]:=Round(d[i]*w_scale);
    end;
 
    CloseFile(filehnd);
 
    Canvas.Brush.Color:=clWhite;
    Canvas.Rectangle(50,30,Form9.Width-50,Form9.Height-120);
    Canvas.Brush.Color:=clRed;
    Canvas.Pen.Color:=clRed;
    Canvas.Brush.Style:=bsSolid;
 
//Point
    for i:=0 to num-1 do
    begin
    Canvas.Ellipse(a[i]+30,Form9.Height-b[i],a[i]+30+8,Form9.Height-b[i]-8);
    Canvas.MoveTo(a[i]+4+30,Form9.Height-b[i]-4);
    if(i<>num-1) then Canvas.LineTo(a[i]+4+30,Form9.Height-b[i+1]-4);
    end;
    Canvas.Brush.Color:=clBtnFace;
    Canvas.Pen.Color:=clBlack;
 
//Vert_lines
for i:=0 to num-1 do
begin
Canvas.MoveTo(a[i]+4+30,30);
if i=0 then
begin
Canvas.LineTo(a[i]+30+4,Form9.Height-120);
Canvas.TextOut(a[i]+30,Form9.Height-110,inttostr(d[i]));
end;
if (i>0) and ((abs(a[i]-a[i-1]))>10) then
begin
if ((i mod 2)=0) then
begin
Canvas.LineTo(a[i]+30+4,Form9.Height-120);
Canvas.TextOut(a[i]+30,Form9.Height-110,inttostr(d[i]));
end;
end;
end;
 
//Horiz_lines
for i:=0 to num-1 do
begin
Canvas.MoveTo(50,Form9.Height-b[i]-4);
if (i=0) then
begin
Canvas.LineTo(Form9.Width-50,Form9.Height-b[i]-4);
Canvas.TextOut(0,Form9.Height-b[i]-4,floattostr(c[i]));
end;
if (i>0) and ((abs(b[i]-b[i-1]))>5) then
begin
if ((i mod 2)=0) then
begin
Canvas.LineTo(Form9.Width-50,Form9.Height-b[i]-4);
Canvas.TextOut(0,Form9.Height-b[i]-4,floattostr(c[i]));
end;
end;
end;
 
Label1.Caption:='Математическое ожидание = '+FloatToStr(MO)+#10+'Дисперсия = '+FloatToStr(DISP);
end;
 
end.