| Author | Comment |
Vectris
Ultralisk
Posted: 6 Jan 2009
17:10 GMT
Total Posts: 375 | Well, not from the homescreen, but if you have the application SciTools and you use the Sig. Fig. Calculator, 20-19 causes a RAM Clear.
For anyone who knows what significant figures are, what would the answer be? I'm pretty sure it's 0 but I find it hilarious that the calculator can't do it. Also 20-18 creates a link error and the cursor get jammed on the Application Menu. God knows what 20-17 does. |
BrandonW
Goliath
Posted: 7 Jan 2009
18:47 GMT
Total Posts: 100 | I know absolutely nothing about SciTools, but when I start it and choose Sig Fig Calculator, and enter "20-19", I just get "INPUT ERROR." What version are you using? Am I entering it incorrectly? Do you have other hooks, programs, or applications installed? Have you tried it on a freshly reset (RAM and archive) calculator? Emulated?
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Vectris
Ultralisk
Posted: 7 Jan 2009
20:36 GMT
Total Posts: 375 | I was doing it on my TI-84+SE. I know it's not something else interfering because this question even stumped my chemistry teacher, who is the one who taught us significant figures. When dealing with significant figures 20 - 1 = 20 and other weird things like that, I guess the SciTools programmers forgot that 20 - 19 should be 0 and they didn't include anything for problems like that (20 - 18, 10 - 9, etc.). It's a matter of the program not knowing how to calculate it, not a loophole or bug in the program, well it's kind of a bug but something left out really. |
me2
Goliath
Posted: 8 Jan 2009
09:47 GMT
Total Posts: 171 | A significant figure is
(1)A nonzero number;
(2)A zero between two significant figures:viz., a nonzero number or a zero that has been made significant;or
(3)All zeros to the right of the decimal point
20-19=1
20 has one sig fig. 19 has two sig figs. When subtracting or adding, use the significant figures to the most exact number of the operated-upon numbers. So 20-19 is 1, not 1.0
When multiplying or dividing, use the number with the least significant figures to find the sig figs in the answer (so 20*19=400 because 400 has only one sig fig, just like 20)
4001 has 4 sig figs
4000 has one sig fig
100.0 has four sig figs
1 has one sig fig
0.009 has three sig figs
Hope that helps you with significant figures, and perhaps the programmer with their program.
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<--- Going out with a bang. |
Vectris
Ultralisk
Posted: 8 Jan 2009
15:53 GMT
Total Posts: 375 | Thanks but I knew all of that. The only thing is that I still don't see how 20-19 is 1 instead of 0.
When you do adding and subtracting you round to the closest significant figure to the left.
100
-25
75
but since 1 is closest to the left, or w/e, you round the place behind it, in this case, the ten's place with 7, so you round up and 100 - 25 = 100. Thus, 100 - 99 should also be 0 since you round the 1 down, really there's nothing in the ten's place to round so 0 is 0. |
BrandonW
Goliath
Posted: 9 Jan 2009
13:44 GMT
Total Posts: 100 | Right, well, what I was saying is that I can't duplicate what you're seeing. I want to see it crash for myself...I did what you said and I just got "INPUT ERROR", so what do I have to do step-by-step on a freshly-reset 84+SE to recreate it?
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Vectris
Ultralisk
Posted: 9 Jan 2009
17:51 GMT
Total Posts: 375 | Nothing, just 20-19. I guess the error varies per calculator or something. I get the same results every try on 20 - 19 though. 20 - 18 is the really weird one where the application menu freezes but the cursor still blinks in the upper left, but you can't do a thing except turn off the calc. and when it turns back on you get your RAM cleared. 20 - 19 just RAM clears.
Try 20 - 17 etc. all the way to 15 or 14 if you want to see what random stuff you can get. |
BrandonW
Goliath
Posted: 10 Jan 2009
16:33 GMT
Total Posts: 100 | I still get nothing. What OS version are you on?
Could you please try it with the TI-83 Plus Flash Debugger and see if you still get it, and if so, tell me how to do it?
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me2
Goliath
Posted: 15 Jan 2009
11:15 GMT
Total Posts: 171 | 20-19 is 1 in sig figs because the lowest sig fig in the problem is 9: a figure in the units column. Therefore, the answer's smallest figure must be in the units column.
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<--- Going out with a bang. |
Vectris
Ultralisk
Posted: 15 Jan 2009
15:25 GMT
Total Posts: 375 | Well the lowest sf (sig fig, super short) is actually 1, but I get what you mean, however that's not what I was thinking.
Our teacher taught it that you start from the right side (0 and 9) and work your way left digit by digit until both digits are sfs. Now the first set, 0 and 9, are not both sig figs, thus you would go to the next, 2 and 1 are sfs so that is the place that you would round it too. And when rounding 1 to the tens place, it would round down to 0. That's my logic behind it, basically just round to the column that contains all sig figs, in this case the tens column with 2 and 1.
Anyways our teacher said doing addition with sfs was kind of weird so there may be a deeper explanation that he didn't tell us about. |
