john135246 2008-10-23 17:07
vb超高精度计算
我想做个程序，用 4（1-1/3+1/5。。。。。+1/2n-1）的式子算圆周率
用Timer每豪秒算一步，算n长时间使它变得极其精确
但Double只能到15位
有谁有办法达到超高的精度？（越高越好，10000位都行）
（据说string可以，但实在想不出怎么用）
Nothing 2008-10-23 21:48
[color=#000000][color=#0000ff]Private[/color] [color=#0000ff]Sub[/color] Command1_Click[color=#0000cc]([/color][color=#0000cc])[/color]
getpi [color=#ff0000]CLng[/color][color=#0000cc]([/color][color=#ff0000]InputBox[/color][color=#0000cc]([/color][color=#ff00ff]"生成多少位数（1-50000）的PI？"[/color][color=#0000cc],[/color] [color=#ff00ff]"提示"[/color][color=#0000cc],[/color] 30000[color=#0000cc])[/color][color=#0000cc])[/color]
[color=#0000ff]End[/color] [color=#0000ff]Sub[/color]
[color=#0000ff]Sub[/color] getpi[color=#0000cc]([/color]Optional [color=#0000ff]ByVal[/color] nums As Long [color=#0000cc]=[/color] 10000[color=#0000cc])[/color]
nums [color=#0000cc]=[/color] nums [color=#0000cc]\[/color] 5
[color=#0000ff]Dim[/color] max As Long[color=#0000cc],[/color] laptime As Single[color=#0000cc],[/color] result[color=#0000cc]([/color][color=#0000cc])[/color] As [color=#ff0000]String[/color]
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laptime [color=#0000cc]=[/color] Timer
max [color=#0000cc]=[/color] 18 [color=#0000cc]*[/color] nums
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result[color=#0000cc]([/color]0[color=#0000cc])[/color] [color=#0000cc]=[/color] [color=#ff00ff]"π="[/color] [color=#0000cc]&[/color] vbCrLf
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d [color=#0000cc]=[/color] 2 [color=#0000cc]*[/color] i [color=#0000cc]+[/color] 1
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k [color=#0000cc]=[/color] k [color=#0000cc]+[/color] 1
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[color=#0000ff]If[/color] k [color=#0000ff]Mod[/color] 200 [color=#0000cc]=[/color] 0 [color=#0000ff]Then[/color] result[color=#0000cc]([/color]k[color=#0000cc])[/color] [color=#0000cc]=[/color] result[color=#0000cc]([/color]k[color=#0000cc])[/color] [color=#0000cc]&[/color] [color=#ff00ff]"---["[/color] [color=#0000cc]&[/color] k [color=#0000cc]*[/color] 5 [color=#0000cc]&[/color] [color=#ff00ff]"]---"[/color] [color=#0000cc]&[/color] vbCrLf
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Me[color=#0000cc].[/color]Caption [color=#0000cc]=[/color] [color=#ff00ff]"计算完毕！总计用时"[/color] [color=#0000cc]&[/color] Timer [color=#0000cc]-[/color] laptime [color=#0000cc]&[/color] [color=#ff00ff]"秒！"[/color]
[color=#0000ff]End[/color] [color=#0000ff]Sub[/color]
[/color]