Re: Precision

*To*: mathgroup at smc.vnet.net*Subject*: [mg129365] Re: Precision*From*: Ray Koopman <koopman at sfu.ca>*Date*: Mon, 7 Jan 2013 23:07:20 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <kc8k2f$b17$1@smc.vnet.net>

On Jan 4, 11:17 pm, Rob Ryan <tio54... at gmail.com> wrote: > My frustration is growing. I simply want to add (for example): > 103971.66+52282.64+2998.27. These are dollars and cents and I'd > like to keep the cents. But when I input that line, I get 159923. > When I input: N[(103971.66+52282.64+2998.27),20] I STILL get 159923. > What do I do to get 159952.57? I've used "SetPrecision", etc. > with still no result. > I note that when I type 103971.66 and hit shift-return, the > output is 103972. If I then type "InputForm[%]" I get 103971.66. > > There simply has to be an easy way to add these numbers - > any calculator watch can do it! If you want the cents to *always* print, use PaddedForm with an explicit request for 2 digits to the right of the decimal point. s = 103971.66 + 52282.64 + 2998.27 NumberForm[s,8] 159253. 159252.57 t = s + .43 NumberForm[t,8] NumberForm[t,{8,2}] PaddedForm[t,{8,2}] 159253. 159253. 159253. 159253.00