Re: Gaussian Distribution Using Dice
- Posted by cklester <cklester at yahoo.com> Jul 30, 2004
- 481 views
This looks good, but, again, I don't understand the last math part... http://mathforum.org/library/drmath/view/52207.html I'd just like a FAST function like this: aNumber = 13 -- what's the odds of the sum of 13 sides = 6 -- appearing when 6-sided dice rolls = 4 -- are rolled 4 times and added together? xFromY = instances( aNumber, sides, rolls ) Right now, I'm using a recursive algorithm, as follows: -- start of code -- code generated by Win32Lib IDE v0.18.20 include Win32Lib.ew without warning -------------------------------------------------------------------------------- -- Window Window1 constant Window1 = createEx( Window, "Window1", 0, Default, Default, 357, 300, 0, 0 ) constant statBar = createEx( StatusBar, "StatusBar8", Window1, 0, 0, 0, 0, 0, 0 ) constant txt_Rolls = createEx( EditText, "3", Window1, 52, 12, 48, 20, 0, 0 ) constant txt_Faces = createEx( EditText, "6", Window1, 52, 36, 48, 20, 0, 0 ) constant LText4 = createEx( LText, "Faces", Window1, 12, 40, 40, 20, 0, 0 ) constant LText5 = createEx( LText, "Rolls", Window1, 12, 16, 36, 20, 0, 0 ) constant LText6 = createEx( LText, "Distribution", Window1, 12, 72, 68, 20, 0, 0 ) constant pix_Graph = createEx( Pixmap, "pix_Graph", Window1, 216, 8, 100, 28, 0, 0 ) sequence IDEFlags IDEFlags = classDefaults( Window, { {1, {WS_SYSMENU}},{2, {0}} } ) constant CWindow14 = createEx( Window, "CWindow14", Window1, 8, 92, 340, 160, or_all({WS_CHILD, WS_CLIPSIBLINGS, WS_BORDER}), 0 ) openWindow(CWindow14, Normal) moveZOrder( CWindow14, HWND_TOP) --------------------------------------------------------- -------------------------------------------------------------------------------- include xcontrols.ew include get.e object junk sequence rect, origin integer x, y, width, height, pixX, pixY constant GMID = xControl( Geometry, "", Window1, 0, 0, 0, 0, 0, 0 ), GMIDc = xControl( Geometry, "", CWindow14, 0, 0, 0, 0, 0, 0 ) manage( GMID, CWindow14, {0.0, 0}, {0, 90}, {1.0, 00}, {1.0 , 0} ) manage( GMIDc, pix_Graph, {0.0, 0}, {0.0, 0}, {1.0, 0.0}, {1.0 , 0.0} ) rect = getCtlSize(CWindow14) width = rect[1] height = rect[2] setCtlSize( pix_Graph, width, height ) setPenColor( pix_Graph, Black ) function sum(sequence s) integer result result = 0 for t=1 to length(s) do result += s[t] end for return result end function function increment(sequence face, integer which, integer max) face[which] += 1 if face[which] > max then if which > 1 then face[which] = 1 face = increment(face,which-1,max) end if end if return face end function function getMaxIndex(sequence s) atom result, max max = -999999 result = 0 for t=1 to length(s) do if s[t] > max then max = s[t] result = t end if end for return result end function function getMax(sequence s) atom max max = -999999 for t=1 to length(s) do if s[t] > max then max = s[t] end if end for return max end function procedure plotGraph() integer min, max, range, result, sides, rolls, toOne, thickness sequence faces, results, dice, plotBase, plotPoint atom scale rect = getCtlSize(CWindow14) width = rect[1] height = rect[2] origin = { 1 , height-1 } -- get values sides = getNumber(txt_Faces) rolls = getNumber(txt_Rolls) if sides > 0 and rolls > 0 and rolls <= 3 then min = rolls max = min * sides range = max - min + 1 toOne = rolls - 1 thickness = floor(width / range) -- plot graph dice = repeat(1,rolls) results = repeat(0,range) while dice[1] != ( sides + 1 ) do -- for 3d6, starts with {1,1,1} result = sum(dice) results[result-toOne]+=1 dice = increment(dice,rolls,sides) end while scale = height / getMax(results) --plot the results clearWindow(pix_Graph) clearWindow(CWindow14) for t=1 to length(results) do plotBase = origin + {(t-1) * thickness,0} plotPoint = origin + { plotBase[1]+thickness, floor(-results[t]*scale) } if t/2 = floor(t/2) then setPenColor(pix_Graph,Blue) else setPenColor(pix_Graph,Black) end if drawRectangle(pix_Graph,w32True,plotBase[1],plotBase[2],plotPoint[1],plotPoint[2]) copyBlt(CWindow14, 1, 1, pix_Graph ) end for setText(statBar, sprintf("%d,%d",origin)) end if end procedure -------------------------------------------------------------------------------- procedure Window1_onPaint (integer self, integer event, sequence params)--params is ( int x1, int y1, int x2, int y2 ) plotGraph() end procedure setHandler( Window1, w32HPaint, routine_id("Window1_onPaint")) -------------------------------------------------------------------------------- procedure Window1_onActivate (integer self, integer event, sequence params)--params is () plotGraph() end procedure setHandler( Window1, w32HActivate, routine_id("Window1_onActivate")) -------------------------------------------------------------------------------- procedure txt_Rolls_onChange (integer self, integer event, sequence params)--params is () plotGraph() end procedure setHandler( txt_Rolls, w32HChange, routine_id("txt_Rolls_onChange")) -------------------------------------------------------------------------------- procedure txt_Faces_onChange (integer self, integer event, sequence params)--params is () plotGraph() end procedure setHandler( txt_Faces, w32HChange, routine_id("txt_Faces_onChange")) -------------------------------------------------------------------------------- procedure CWindow14_onResize (integer self, integer event, sequence params)--params is ( int style, int cx, int cy ) plotGraph() end procedure setHandler( CWindow14, w32HResize, routine_id("CWindow14_onResize")) WinMain( Window1,Normal ) --end of code -=ck "Programming in a state of EUPHORIA." http://www.cklester.com/euphoria/