Texas Instruments TI-92+, Список советов

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Properties Function
(Credit to Frank Westlake)
[9.9] Display all 14 significant digits
The TI89/92+ perform floating point calculations with 14 significant digits of resolution. However, you
cannot set the display mode format to show all these digits. The regression calculations, however, do
display all 14 digits.
You can see all 14 digits for a number in the history area, though - just return it to the command line.
For example, if the display mode is set to Float 12, then entering 'pi' will display
3.14159265359
but if you select it in the history area, it is shown in the command line as
3.1415926535898
Note that, in general, these 2 extra digits are probably not accurate or significant. Any computer or
calculator that performs floating point arithmetic includes one or two 'guard digits'. These digits are
used during calculations to eliminate or reduce round-off errors, especially during long calculation
sequences. That is why the 89/92+ use them during calculations, but do not normally let you display
them.
[9.10] Group fraction digits for easier reading
If you often work with numbers with many digits, it is tedious and tiresome to read the numbers and
copy them without making a mistake. These two routines help somewhat, by converting the number to
a string with spaces between the fractional digits. I show two routines:
grpfrc(x,f) Is a function that returns x as a string, with groups of f digits. This routine
is best used in a program, for displaying results.
grpfrcan() Shows the latest answer in the history display as a string with grouped fraction
digits. This routine is best used from the command line, to display the last
answer. The number of group fraction digits is fixed, but can be easily changed
9 - 10