Re: trouble using fPart on TI-82
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This is due to the internal precision and rounding. The TI-82 displays 10
digits, but stores 13 for caculations. The TI-85 displays 11 digits. I
have a TI-85, and got:
display internal (last 4 digits)
1.117 647 058 82 (8235)
.117 647 058 824 (8235)
8.500 000 000 00 (+2.1e-12)
.500 000 000 002 (0021)
1.999 999 999 99 (9916)
.999 999 999 992 (9916)
^
+--------------------------------------------------------+
The TI-82 has a lower display precision, and cuts off (rounds) here: -+
Which, on the last step, takes .9999... and rounds to 1. Unfortunate, but
true. Never trust the calculator. =)
At 16:34 9/21/96 -0500, Paul E Kehle wrote:
>Hello, Can anyone help me with this problem? Grab your TI-82 and
>confirm the following:
>
>19/17 ENTER
>1.117647059
>
>fPart Ans ENTER
>.117647059
>
>Ans ^-1 ENTER
>8.5
>
>fPart Ans ENTER
>.5
>
>Ans ^-1 ENTER
>2
>
>fPart Ans ENTER
>1
>
>!?!? Any ideas how to get around this problem? I assume some internal
>flag is getting in the way of the fPart routine. Technically I guess it's
>correct since 19/17 = 1.11764705882352941176... and not 1.117647059 but
>then it's inconsistent in displaying 8.5 as the reciprocal of .117647059.
>Please either tell me this is a bug on old 82's or help me find a way
>around this problem--meaning a way to get consistent results between
>what the calculator is keeping track of internally and what it displays.
>
>Thank you in advance,
>Paul
>
>
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