Show All Digits (SHOWALLD)
for TI-82
by Robert Hart


  To maximize accuracy, the TI-82, and many calculators, store internally
more digits than they display. In some cases, the extra digits round to a 
more accurate answer. In other cases, the extra undisplayed digits may be
accurate themselves. This program will let you see all fourteen digits of
the current Ans variable.


How to use this program:

While performing normal calculations, you may want to see if the calculator
is "hiding" extra digits that it doesn't normally display. Simply perform
calculations as normal then run prgmSHOWALLD. The current Ans variable will
be displayed in its normal form and in a long form for comparison. In most
cases more digits (up to fourteen) will be shown.


Example 1:

________________     ________________   
1/3               |                    |   You perform a calculation,
     .3333333333  |  1                 |   get an answer, and run
Ans*3             |                    |   the program.
               1  |  .99999999999999   |   
prgmSHOWALLD      |                    |   The program clears the screen
                  |                    |   and shows the normal display
________________  |  ________________  |   and the internal storage.
                                        

In this example the calculator says that (1/3)*3 = 1, but notice that the
calculator actually stores .99999999999999. This is an example why
calculators use extra digits for accuracy. The normally displayed answer
is more correct.


Example 2:

________________     ________________   
e^1:prgmSHOWALLD  |                    |   You want to see the
                  |  2.718281828       |   "hidden" digits of the
                  |                    |   constant e.
                  |  2.718281828459    |   
                  |                    |   The program shows three
                  |                    |   more digits than normal.
________________  |  ________________  |
                                        

Notice that in this example only thirteen digits are shown. The last
internal digit is a zero. The program will not display any trailing zeros.


Usefulness of the program:

The usefulness of the four extra digits is trivial in most calculations.
The 14th digit may or may not be rounded, and therefore, it's probably
best to just use the normal display for calculations. However, it is
interesting to be able to see the "hidden" digits the calculator stores.


Notes:

1. The program needs no input, it simply uses the current Ans variable.
2. The value of Ans is the same at the end of the program if you wish to
     continue calculations.
3. The following variables are modified during program execution:
     A, B, C, D, E, L, R, and S.


Author:

Robert Hart
http://people.smu.edu/rnhart/