[Java Paint] drawing function image

Using the graphics class to draw any explicit function image, just modify the F () function in the code, and adjust the Timesx and Timesy parameters to zoom in or out of the image in the direction. You need to redefine the coordinate system.

1  Packagetest;2 3 Importjavax.swing.*;4 ImportJava.awt.Graphics;5 6  Public classDrawfunctionextendsJFrame {7     Static DoubleTimesx = ten, Timesy = 10;8     DoubleFDoublex) {9         returnMath.sin (x)/Math.pow (1.1,-X);//function ExpressionTen     } One     intx0, y0; A     Static intW = 600, H =; -     Static DoubleL =-W/2, R = W/2; - Graphics G; the      Public voidSetorigin (intXinty) { -          This. x0 =x; -          This. y0 =y; -         //Show coordinate axis +DrawLine (-W/2, 0, W/2, 0); -DrawLine (0,-H/2, 0, H/2); +DrawString ("X", W/2-30,-20); ADrawString ("Y", -20, H/2-20); at          for(inti = 1; I <= 10; i + +) { -Draw (W/2-i-6, i); -Draw (W/2-i-6,-i); -         } -          for(inti = 1; I <= 10; i + +) { -Draw (-I, H/2-i); inDraw (I, H/2-i); -         } to     } +      Publicdrawfunction () { -AddNewNewpanel ()); the     } *      Public Static voidMain (string[] args) { $Drawfunction frame =Newdrawfunction ();Panax NotoginsengFrame.settitle ("Drawfunction"); - frame.setsize (W, H); theFrame.setlocationrelativeto (NULL); + frame.setdefaultcloseoperation (jframe.exit_on_close); AFrame.setvisible (true); theFrame.setresizable (false); +     } -      Public classcoordinate2d { $         intx, y; $          PublicCoordinate2d (intXinty) { -              This. x =x; -              This. y =y; the         } -          Public intGetpixelpointx () {Wuyi             returnX0 +x; the         } -          Public intGetpixelpointy () { Wu             returnY0-y; -         } About     } $     classNewpanelextendsJPanel { -         protected voidpaintcomponent (Graphics g) { -             Super. paintcomponent (g); -G =G; ASetorigin (W/2, H/2); +             //in the following, draw what want draw! the              for(inti =-W/2; I <= W/2; i + +) { - Draw (I, work (i)); $             } the             /* the for (int i = 0; i <; i + +) { the int x = (int) (Math.random () * 400-200); the int y = (int) (Math.random () * 400-200); - drawstring ("haha", x, y); in             } the             */ the         } About     } the     intWorkintx) { the         //timesx = 0.01; the         //Timesy = +; +         return(int) (F (X/TIMESX) *timesy); -     } the      Public voidDrawintXinty) {Bayi         intX =Newcoordinate2d (x, y). Getpixelpointx (); the         intY =Newcoordinate2d (x, y). Getpixelpointy (); the g.drawline (x, y, x, y); -     } -      Public voidDrawrec (intX1,intY1,intX2,inty2) { the         intDX = x1 < x2? 1:-1; the         intdy = y1 < y2? 1:-1; the          for(inti = x1; I! = x2 + dx; i + =dx) { the              for(intj = y1; J! = y2 + dy; J + =dy) { - Draw (I, j); the             } the         } the     }94      Public voidDrawLine (intX1,intY1,intX2,inty2) { the         intDX = x1 < x2? 1:-1; the         if(X1 = =x2) Drawrec (x1, y1, x2, y2); the         Else {98             DoubleD = (Double) (y2-y1)/(X2-x1); About              for(inti = x1; I! = x2 + dx; i + =dx) { -Draw (I, (int) (Y1 + (i-x1) *d));101             }102         }103     }104      Public voidDrawString (String s,intXinty) { the         intX =Newcoordinate2d (x, y). Getpixelpointx ();106         intY =Newcoordinate2d (x, y). Getpixelpointy ();107 g.drawstring (S, X, Y);108     }109}

[Java Paint] drawing function image