[GLaforge]

Hi,
hab hier ein Programm für euch zum testen. Das Programm kann Gleichungen bis zum dritten Grad(kubische Gleichung) lösen,d.h. Ableitung,Wendepunkt,Extrema und Nullstellen. Das Programm kann bei einer kubischen Gleichung bis jetzt aber nur eine Nullstelle.
Das Prog besteht aus zwei Forms, eine Graph-Form und eine Rechen-Form. Die Graph-Form zeigt den Graphen in einen selbst-wählbaren Intervall an.
Ich denke es gibt noch genügend Eckpunkte die zu bearbeiten sind,einige sind mir auch bekannt z.Bsp. das Intervall welches nicht z.b. 1...4 lauten kann.
Also probiert bitte aus und übt konstruktive Kritik, denn nur die macht mein Programm besser. Desweiteren muss ich noch sagen, dass äußerst wenig Kommentartexte vorhanden sind- hoffe ihr durchschaut das Prog trotzdem.

cu




PSas Prog ist zur Zeit bei mir Inhalt des Info-Unterrichts, deswegen ist nicht der gesamte QT auf meinem Mist gewachsen.

Ich hoffe ihr seit schon eifrig am probieren.

ja ist ganz nett was die zeichnung anbelangt ALLERDINGS: grausliches Design, sorry aber da ist zuviel leer

@Nicodius: Yeep, das Design ist noch praktisch garnicht vorhanden.Mir ging es bisher aber auch nur um die Funktionalität.

MfG

"," sollte bei der eingabe durch "." ersetzt werden, weil es sonst falsch berechnet !?

@StefanDP Ist vermerkt, danke!

aber für mich ist das echt praktisch danke, bringt nämlich viel und ist auch nett durchzutesten(wegen der grafischen ausgabe)-- ist wie ein kleines spiel

Grausam. Hast du vorher in Basic programmiert:

zusammenfalten · markieren

Delphi-Quellcode:

procedure TForm1.ButtonRechneClick(Sender: TObject);
Var a,b,c,d,a1,b1,a2,xw,yw,xmax,ymax,xmin,ymin:extended;
    x1,x2,x3,y1,y2,y3,G:extended;
    code:integer;
    s1,s2,s3,s4,s5,s6,s7,s8,s9,s10:string;
    s11,s12,s13,s14,s15,s16:string;
    i,xl,xr,yu,yo,my,mx,xBo,yBo,xB,yB:integer;
    x,y,F,zw,x4,x5,x6,y4,y5,y6:extended;
    rect:TRect;
begin
Labelxmax.Caption:='';
Labelxmin.Caption:='';
Labelxw.Caption:='';Labelyw.Caption:='';
Labelnst1.Caption:='';
Labelnst2.Caption:='';Labelnst3.Caption:='';
rect:= Bounds(0,0,Image1.Width,Image1.Height);
Image1.Canvas.Brush.Style:=bsClear;
Image1.Canvas.Brush.Color:=clwhite;
Image1.Canvas.FillRect(rect);
Val(Edita.Text,a,code);
Val(Editb.Text,b,code);
Val(Editc.Text,c,code);
Val(Editd.Text,d,code);
Str(a:4:1,s1);Edita1.Text:=s1;
Str(b:4:1,s2);Editb1.Text:=s2;
Str(c:4:1,s3);Editc1.Text:=s3;
Str(d:4:1,s4);Editd1.Text:=s4;
a1:=a*3;b1:=b*2;a2:=a1*2;
Str(a1:4:1,s5);Editastrich.Text:=s5;
Str(b1:4:1,s6);Editbstrich.Text:=s6;Editcstrich.Text:=s3;
Str(a2:4:1,s7);Editastrich2.Text:=s7;
Editbstrich2.Text:=s6;Editastrich3.Text:=s7;
With Form1.Image1 Do //Graph-Zeichnung
begin
mx:= Image1.ClientWidth div 8;
my:= Image1.ClientHeight div 8;
With Canvas Do
begin
Pen.Style:=psDot;
Pen.Color:=clblue;
Pen.Width:=1;
for i:=0 to 8 do
begin
MoveTo(i*mx,0);LineTo(i*mx,height);
end;
for i:= 0 to 8 do
begin
MoveTo(0,i*my);LineTo(width,i*my);
end;
xBo:= round (4*mx);
yBo:= round (4*my);
Pen.Style:=psSolid;
Pen.Width:=2;
Font.Color:=clblue;
Font.Style:=[fsbold];
MoveTo(0,yBo);LineTo(width,yBo);//x-Achse
MoveTo(xBo,0);LineTo(xBo,height);//y-Achse
TextOut(xBo-15,5,'y');TextOut(ClientWidth -15,yBo+5,'x');
TextOut(xBo+mx,yBo+10,'1');TextOut(xBo-mx,yBo+10,'-1');
TextOut(xBo-20,yBo+my-5,'-1');TextOut(xBo-10,yBo-my-5,'1');
MoveTo(xBo,0);LineTo(xBo-4,10);
MoveTo(xBo,0);LineTo(xBo+4,10);//y-Pfeil
MoveTo(Width,yBo);LineTo(Width-10,yBo-4);
MoveTo(Width,yBo);LineTo(Width-10,yBo+4);//x-Pfeil
For xB:=0 to width Do
begin
x:=xB/mx-4;
y:=a*x*x*x+b*x*x+c*x+d;
yB:=trunc((4-y)*my);
if xB=0 then MoveTo(xB,yB)
        else begin Pen.Color:=clblack;
                   LineTo(xB,yB);
             end;
end;
end; // With Canvas Do
end; // With Form2.Image1 Do
if a2=0 then begin Labelxw.Caption:=' / '; //Wendepunkt
                   Labelyw.Caption:=' / ';
             end
        else begin xw:=-b1/a2;
                   yw:=a*xw*xw*xw+b*xw*xw+c*xw+d;
                   Str(xw:4:2,s8);Str(yw:4:2,s9);
                   Labelxw.Caption:=s8;Labelyw.Caption:=s9;
             end;
if a=0 then begin if b=0 then begin //Extrema
                               Labelxmin.Caption:='kein Extrema';
                              end
                         else begin
                               if b<0 then begin
                                            x:=-c/b1;
                                            y:=a*x*x*x+b*x*x+c*x+d;
                                            Str(x:4:2,s10);Str(y:4:2,s11);
                                            Labelxmax.Caption:='Maximum ( '+s10+
                                            ' | '+s11+ ' )';
                                           end
                                      else begin
                                            x:=-c/b1;
                                            y:=a*x*x*x+b*x*x+c*x+d;
                                            Str(x:4:2,s10);Str(y:4:2,s11);
                                            Labelxmin.Caption:='Minimum ( '+s10+
                                            ' | '+s11+ ' )';
                                           end;
                              end;
            end
       else begin
             G:=b1*b1-4*a1*c;
             if G=0 then begin
                          x:=-b1/(2*a1);
                          zw:=a2*x+b1;
                          if zw<0 then begin
                                        y:=a*x*x*x+b*x*x+c*x+d;
                                        Str(x:4:2,s10);Str(y:4:2,s11);
                                        Labelxmax.Caption:='Maximum ( '+s10+
                                        ' | '+s11+ ' )';
                                       end
                                  else begin
                                        y:=a*x*x*x+b*x*x+c*x+d;
                                        Str(x:4:2,s10);Str(y:4:2,s11);
                                        Labelxmin.Caption:='Minimum ( '+s10+
                                        ' | '+s11+ ' )';
                                       end;
                         end
                    else begin
                          if G<0 then begin
                                       Labelxmin.Caption:='kein Extrema';
                                      end
                                 else begin
                                       x1:=(-b1+sqrt(G))/(2*a1);
                                       x2:=(-b1-sqrt(G))/(2*a1);
                                       y1:=a2*x+b1;
                                       y2:=a2*x1+b1;
                                       if y1>0 then
                                            begin
                                            y:=a*x1*x1*x1+b*x1*x1+c*x1+d;
                                            Str(x1:4:2,s10);Str(y:4:2,s11);
                                            Labelxmin.Caption:='Minimum ( '+s10+
                                            ' | '+s11+ ' )';
                                            end
                                               else
                                            begin
                                            y:=a*x1*x1*x1+b*x1*x1+c*x1+d;
                                            Str(x1:4:2,s10);Str(y:4:2,s11);
                                            Labelxmax.Caption:='Maximum ( '+s10+
                                            ' | '+s11+ ' )';
                                            end;
                                       if y2>0 then
                                            begin
                                            y:=a*x2*x2*x2+b*x2*x2+c*x2+d;
                                            Str(x2:4:2,s12);Str(y:4:2,s13);
                                            Labelxmax.Caption:='Maximum ( '+s12+
                                            ' | '+s13+ ' )';
                                            end
                                               else
                                            begin
                                            y:=a*x2*x2*x2+b*x2*x2+c*x2+d;
                                            Str(x2:4:2,s12);Str(y:4:2,s13);
                                            Labelxmin.Caption:='Minimum ( '+s12+
                                            ' | '+s13+ ' )';
                                            end;
                                      end;
                         end;
            end;
if a<>0 then begin
             x1:=-100;x2:=100;
             repeat //Bisektion
              x3:=(x1+x2)/2;
              y1:=a*x1*x1*x1+b*x1*x1+c*x1+d;
              y2:=a*x2*x2*x2+b*x2*x2+c*x2+d;
              y3:=a*x3*x3*x3+b*x3*x3+c*x3+d;
               if (y1<0) and (y3>0) and (y2>0) then
                 begin x1:=x1;x2:=x3;
                 end;
               if (y1<0) and (y3<0) and (y2>0) then
                 begin x1:=x3;x2:=x2;
                 end;
               if (y1>0) and (y3>0) and (y2<0) then
                 begin x1:=x2;x2:=x3;
                 end;
               if (y1>0) and (y3<0) and (y2<0) then
                 begin x1:=x3;x2:=x1;
                 end;
             until abs(y3)<0.000000001;
                  Str(x3:4:2,s14);
                  Labelnst1.Caption:='x1= '+s14;
            end
       else if b>0 then begin x1:=(-c+sqrt(c*c-4*b*d))/(2*b);
                              x2:=(-c-sqrt(c*c-4*b*d))/(2*b);
                              Str(x1:4:1,s14);Str(x2:4:1,s15);
                              Labelnst1.Caption:='x1= '+s14;
                              Labelnst2.Caption:='x2= '+s15;
                        end
                   else begin x1:=-d/c;
                              Str(x1:4:1,s14);
                              Labelnst1.Caption:='x1= '+s14;
                        end;
end;

(Formatierung unverändert.) Wie behältst du da die Übersicht wo ein Block zu ende ist und der nächste anfängt bzw. welches end zu welchem begin gehört?

Hier noch mal "korrekt" formatiert. Kuck dir mal den Unterchied an:

zusammenfalten · markieren

Delphi-Quellcode:

procedure TForm1.ButtonRechneClick(Sender: TObject);
var
  a, b, c, d, a1, b1, a2, xw, yw, xmax, ymax, xmin, ymin: extended;
  x1, x2, x3, y1, y2, y3, G: extended;
  code: integer;
  s1, s2, s3, s4, s5, s6, s7, s8, s9, s10: string;
  s11, s12, s13, s14, s15, s16: string;
  i, xl, xr, yu, yo, my, mx, xBo, yBo, xB, yB: integer;
  x, y, F, zw, x4, x5, x6, y4, y5, y6: extended;
  rect: TRect;
begin
  Labelxmax.Caption := '';
  Labelxmin.Caption := '';
  Labelxw.Caption := '';
  Labelyw.Caption := '';
  Labelnst1.Caption := '';
  Labelnst2.Caption := '';
  Labelnst3.Caption := '';
  rect := Bounds(0, 0, Image1.Width, Image1.Height);
  Image1.Canvas.Brush.Style := bsClear;
  Image1.Canvas.Brush.Color := clwhite;
  Image1.Canvas.FillRect(rect);
  Val(Edita.Text, a, code);
  Val(Editb.Text, b, code);
  Val(Editc.Text, c, code);
  Val(Editd.Text, d, code);
  Str(a: 4: 1, s1);
  Edita1.Text := s1;
  Str(b: 4: 1, s2);
  Editb1.Text := s2;
  Str(c: 4: 1, s3);
  Editc1.Text := s3;
  Str(d: 4: 1, s4);
  Editd1.Text := s4;
  a1 := a * 3;
  b1 := b * 2;
  a2 := a1 * 2;
  Str(a1: 4: 1, s5);
  Editastrich.Text := s5;
  Str(b1: 4: 1, s6);
  Editbstrich.Text := s6;
  Editcstrich.Text := s3;
  Str(a2: 4: 1, s7);
  Editastrich2.Text := s7;
  Editbstrich2.Text := s6;
  Editastrich3.Text := s7;
  with Form1.Image1 do //Graph-Zeichnung
  begin
    mx := Image1.ClientWidth div 8;
    my := Image1.ClientHeight div 8;
    with Canvas do
    begin
      Pen.Style := psDot;
      Pen.Color := clblue;
      Pen.Width := 1;
      for i := 0 to 8 do
      begin
        MoveTo(i * mx, 0);
        LineTo(i * mx, height);
      end;
      for i := 0 to 8 do
      begin
        MoveTo(0, i * my);
        LineTo(width, i * my);
      end;
      xBo := round(4 * mx);
      yBo := round(4 * my);
      Pen.Style := psSolid;
      Pen.Width := 2;
      Font.Color := clblue;
      Font.Style := [fsbold];
      MoveTo(0, yBo);
      LineTo(width, yBo); //x-Achse
      MoveTo(xBo, 0);
      LineTo(xBo, height); //y-Achse
      TextOut(xBo - 15, 5, 'y');
      TextOut(ClientWidth - 15, yBo + 5, 'x');
      TextOut(xBo + mx, yBo + 10, '1');
      TextOut(xBo - mx, yBo + 10, '-1');
      TextOut(xBo - 20, yBo + my - 5, '-1');
      TextOut(xBo - 10, yBo - my - 5, '1');
      MoveTo(xBo, 0);
      LineTo(xBo - 4, 10);
      MoveTo(xBo, 0);
      LineTo(xBo + 4, 10); //y-Pfeil
      MoveTo(Width, yBo);
      LineTo(Width - 10, yBo - 4);
      MoveTo(Width, yBo);
      LineTo(Width - 10, yBo + 4); //x-Pfeil
      for xB := 0 to width do
      begin
        x := xB / mx - 4;
        y := a * x * x * x + b * x * x + c * x + d;
        yB := trunc((4 - y) * my);
        if xB = 0 then
          MoveTo(xB, yB)
        else
        begin
          Pen.Color := clblack;
          LineTo(xB, yB);
        end;
      end;
    end; // With Canvas Do
  end; // With Form2.Image1 Do
  if a2 = 0 then
  begin
    Labelxw.Caption := ' / '; //Wendepunkt
    Labelyw.Caption := ' / ';
  end
  else
  begin
    xw := -b1 / a2;
    yw := a * xw * xw * xw + b * xw * xw + c * xw + d;
    Str(xw: 4: 2, s8);
    Str(yw: 4: 2, s9);
    Labelxw.Caption := s8;
    Labelyw.Caption := s9;
  end;
  if a = 0 then
  begin
    if b = 0 then
    begin //Extrema
      Labelxmin.Caption := 'kein Extrema';
    end
    else
    begin
      if b < 0 then
      begin
        x := -c / b1;
        y := a * x * x * x + b * x * x + c * x + d;
        Str(x: 4: 2, s10);
        Str(y: 4: 2, s11);
        Labelxmax.Caption := 'Maximum ( ' + s10 +
          ' | ' + s11 + ' )';
      end
      else
      begin
        x := -c / b1;
        y := a * x * x * x + b * x * x + c * x + d;
        Str(x: 4: 2, s10);
        Str(y: 4: 2, s11);
        Labelxmin.Caption := 'Minimum ( ' + s10 +
          ' | ' + s11 + ' )';
      end;
    end;
  end
  else
  begin
    G := b1 * b1 - 4 * a1 * c;
    if G = 0 then
    begin
      x := -b1 / (2 * a1);
      zw := a2 * x + b1;
      if zw < 0 then
      begin
        y := a * x * x * x + b * x * x + c * x + d;
        Str(x: 4: 2, s10);
        Str(y: 4: 2, s11);
        Labelxmax.Caption := 'Maximum ( ' + s10 +
          ' | ' + s11 + ' )';
      end
      else
      begin
        y := a * x * x * x + b * x * x + c * x + d;
        Str(x: 4: 2, s10);
        Str(y: 4: 2, s11);
        Labelxmin.Caption := 'Minimum ( ' + s10 +
          ' | ' + s11 + ' )';
      end;
    end
    else
    begin
      if G < 0 then
      begin
        Labelxmin.Caption := 'kein Extrema';
      end
      else
      begin
        x1 := (-b1 + sqrt(G)) / (2 * a1);
        x2 := (-b1 - sqrt(G)) / (2 * a1);
        y1 := a2 * x + b1;
        y2 := a2 * x1 + b1;
        if y1 > 0 then
        begin
          y := a * x1 * x1 * x1 + b * x1 * x1 + c * x1 + d;
          Str(x1: 4: 2, s10);
          Str(y: 4: 2, s11);
          Labelxmin.Caption := 'Minimum ( ' + s10 +
            ' | ' + s11 + ' )';
        end
        else
        begin
          y := a * x1 * x1 * x1 + b * x1 * x1 + c * x1 + d;
          Str(x1: 4: 2, s10);
          Str(y: 4: 2, s11);
          Labelxmax.Caption := 'Maximum ( ' + s10 +
            ' | ' + s11 + ' )';
        end;
        if y2 > 0 then
        begin
          y := a * x2 * x2 * x2 + b * x2 * x2 + c * x2 + d;
          Str(x2: 4: 2, s12);
          Str(y: 4: 2, s13);
          Labelxmax.Caption := 'Maximum ( ' + s12 +
            ' | ' + s13 + ' )';
        end
        else
        begin
          y := a * x2 * x2 * x2 + b * x2 * x2 + c * x2 + d;
          Str(x2: 4: 2, s12);
          Str(y: 4: 2, s13);
          Labelxmin.Caption := 'Minimum ( ' + s12 +
            ' | ' + s13 + ' )';
        end;
      end;
    end;
  end;
  if a <> 0 then
  begin
    x1 := -100;
    x2 := 100;
    repeat //Bisektion
      x3 := (x1 + x2) / 2;
      y1 := a * x1 * x1 * x1 + b * x1 * x1 + c * x1 + d;
      y2 := a * x2 * x2 * x2 + b * x2 * x2 + c * x2 + d;
      y3 := a * x3 * x3 * x3 + b * x3 * x3 + c * x3 + d;
      if (y1 < 0) and (y3 > 0) and (y2 > 0) then
      begin
        x1 := x1;
        x2 := x3;
      end;
      if (y1 < 0) and (y3 < 0) and (y2 > 0) then
      begin
        x1 := x3;
        x2 := x2;
      end;
      if (y1 > 0) and (y3 > 0) and (y2 < 0) then
      begin
        x1 := x2;
        x2 := x3;
      end;
      if (y1 > 0) and (y3 < 0) and (y2 < 0) then
      begin
        x1 := x3;
        x2 := x1;
      end;
    until abs(y3) < 0.000000001;
    Str(x3: 4: 2, s14);
    Labelnst1.Caption := 'x1= ' + s14;
  end
  else if b > 0 then
  begin
    x1 := (-c + sqrt(c * c - 4 * b * d)) / (2 * b);
    x2 := (-c - sqrt(c * c - 4 * b * d)) / (2 * b);
    Str(x1: 4: 1, s14);
    Str(x2: 4: 1, s15);
    Labelnst1.Caption := 'x1= ' + s14;
    Labelnst2.Caption := 'x2= ' + s15;
  end
  else
  begin
    x1 := -d / c;
    Str(x1: 4: 1, s14);
    Labelnst1.Caption := 'x1= ' + s14;
  end;
end;

PS: Ich habe den langen Code extra gepostet, damit man vergleichen kann. Bitte nicht nach machen im Forum, sondern gegebenenfalls als Anhang anhängen.

aha --> den text hab ich mir noch gar nicht angeschaut

Aus dem Quelltext der anscheinend dabei ist...

Zum Code: Selbst das was ich in BASIC geschrieben habe sah niemals so grausam aus... (Ich weiss das das da oben kein BASIC-Code ist... )

MfG Florian