(11C) Percent of Total [%T]

[Dieter]

(04-18-2018 11:14 AM)Mike (Stgt) Wrote:  Thank you for this one, this relation was new to me, it is surprisingly simple, short and useful.

This is a useful trick that can also be found in other places. The idea is: if you have a routine that multiplies X by a factor, an 1/x before and after the call turn this into a divison. Suppose you have a routine that calculates x*a. Add an 1/x before and after the call, and you get 1/(1/x*a) = x/a.

This comes in handy for unit conversions, and indeed you will find this method already in the respective TI58/59 master library program from 1977.

Example for this method:

LBL A
2
,
5
4
x
RTN

This converts inches to centimeters.

LBL B
1/x
XEQ A
1/x
RTN

This converts centimeters to inches.

The advantage of this method together with "%" (which actually is a simple muliplication with y/100) is that Y is preserved.

Dieter