I remember that a few year ago a calculator was on sale that was specifically designed to make fractional ft-in and probably other PMU (Pile of Medieval Units) calculations. I even think that it was discussed on this list. But I cannot tell anymore which company makes it,
Han ----- Original Message ----- From: "Ma Be" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Wednesday, 2002-02-13 17:32 Subject: [USMA:18194] Re: fractional inch calculators On Tue, 12 Feb 2002 23:39:59 kilopascal wrote: 2002-02-12 I had forgotten, but I have a calculator than can do fractional math. It is a Casio fx-911D Scientific Calculator. I played with it for a while and I must admit, it is very complex and time consuming to do the numeric entries. It does not force results to binary fractions. If you add 1-3/4 to 3-3/5, you get 7-7/20. You can even press a button to convert it to 107/20. If you add a decimal to a fraction, the result is a decimal. There is suppose to be a way to convert fractions to decimals and back, but since I lose the manual, I don't know how to do it. I don't know if this calculator qualifies as the type Marcus is referring to. ... No, evidently not! I do own one of these scientific calculators (it's a Casio, too, BTW!...), but they NEVER stick to binary fractions *necessarily* though. There is a tremendous challenge to setup the "logic" behind doing that. When it comes to doing ordinary fractional operations that is not terribly difficult to setup since there is an unquestionable rule on how to do those. Just program the gizmo to perform that and you're ok. However, there is no such clear-cut way to handle conversions *when* you must present results in binary fractional form! The issue of accuracy of the resulting fraction is what poses that challenge. Depending on the value to be converted the machine would probably have to test several options until it can "decide" on how to present the final binary fraction result. Marcus
