如何绕过HP12CP(F2231AA)计算器进一取整

[jix]

我的目的：需要HP提供方案绕过n进一取整。

譬如，我用它计算pv=1，fv=2，i=8%，PMT=0时n的取值时，照理答案是lg2/lg1.08=9.006，就像说明书注释的0.006>0.005，于是进一得10。虽然从整数年的角度考虑确实应该取整，但CFA、FRM指定的劲敌计算器BA II PLUS可以算到9.006，进不进一交给用户考虑。

https://en.wikipedia.org/wiki/HP-12C#Bugs_and_problems
By design, the HP-12C rounds up the number of payments to the next integer, which produces meaningless results when calculating fractional periods. Consequently, solving for n returns a value that is mathematically incorrect vis-a-vis the standard annuity formula and different from the value returned by other financial calculators, Excel, etc.

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv005.cgi?read=8418
The HP12C always rounds the value of N up to the next whole integer.
The HP12C owners manual (or application manual) has a program that can be keyed in to provide a more "accurate" answer, but the stock HP12C cannot do this.

可能这段（成文于2001年）提到的程序存在于原版套件中，总之我的中文版用户手册里没找见。

[KongL]

用户，您好～

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谢谢

[jix]

那只是报修电话，无法提供技术服务。