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We are still talking past each other, perhaps due to differing terminology. Anyway, enough. It is what it is, WHATEVER that is
No it is not differing terminology, the problem is that ## y=10(1+\operatorname{floor}(\operatorname{abs}(2.5-x))) ## does not look like you think it looks like, it looks like this: https://www.desmos.com/calculator/xausftxwn4phinds said:We are still talking past each other, perhaps due to differing terminology. Anyway, enough. It is what it is, WHATEVER that is
ACK ! You are obviously right. My use of the floor function DID make it different than what I had in my head and your correction of my equation is excellent. Thanks.pbuk said:The function that looks like what you have in your head is ## y=10(0.5+(\operatorname{abs}(2.5-x))) ##.
Thanks but I wanted it to be periodic, like the portion that I showed in the data is a period.phinds said:f(x) = 10 * (1 + floor(abs(2.5-x)))
So if we were to extend the table, row 6 would be a repeat of row 0, right? The cosine solution hits that nicely.MevsEinstein said:Thanks but I wanted it to be periodic, like the portion that I showed in the data is a period.
The periodic data actually has a maximum at x=-0.5 (midway between -1 and 0) and a minimum at x=2.5 (midway between 2 and 3).MevsEinstein said:I was thinking I could use cosine because its maximum is at x=0.
Yes. I tried using the triangle wave, but I couldn't get the numbers to be exact.jbriggs444 said:So if we were to extend the table, row 6 would be a repeat of row 0, right? The cosine solution hits that nicely.
The periodic data actually has a maximum at x=-0.5 (midway between -1 and 0) and a minimum at x=2.5 (midway between 2 and 3).
The periodic version of the piecewise linear fit is a triangle wave. These have the general formMevsEinstein said:Thanks but I wanted it to be periodic, like the portion that I showed in the data is a period.
That's why I can't find the correct one, I thought the period was 5 Thanks for the function!pbuk said:the period which again we know is 6.
To be fair, the period for the given data could be 5. The triangle wave would have a lower maximum, the same slope and the same minimum.MevsEinstein said:That's why I can't find the correct one, I thought the period was 5 Thanks for the function!
As I said, you still know more than we do.MevsEinstein said:The plot is only a portion of the whole function.
What do the data represent ?MevsEinstein said:from my own analysis
I'll give in. The data represents the change from one composite number that has a unit digit of 7 to another one.BvU said:What do the data represent ?
Three problems.MevsEinstein said:The data represents the change from one composite number that has a unit digit of 7 to another one.
7 17 (27) 37 47 (57) 67 (77) (87) 97 107 (117) 127 137 (147) 157 167 (177) (187) 197 (207) (217) 227 (237)
xx 30 20 10 30 30 30 10 20 10 20
I didn't know what @BvU meant until recently. That's why I answered him late. Sorry for the misconveniencejbriggs444 said:Three problems.
1. No, the data in #1 is not consistent with this pattern. In particular, 97 is not composite.
2. The sequence you describe is not periodic.
3. Seriously, dude. When asked what you are really trying to do, an answer is appropriate. Not prolonged evasion. We are 47 posts deep into an irrelevant tangent based on a misunderstanding that could have been corrected if you'd been forthcoming in response to @BvU in post #9.
One would expect this sequence to converge to ... 30, 30, 30, 30, ... with a few 20, 10 and 10, 20 subsequences scattered therein.Code:7 17 (27) 37 47 (57) 67 (77) (87) 97 107 (117) 127 137 (147) 157 167 (177) (187) 197 (207) (217) 227 (237) xx 30 20 10 30 30 30 10 20 10 20
One can get exact values for the cosine model given by @BvU, by inspection.phinds said:Oh. I did not realize that. I'm seeing things in this thread with long strings of digits in real numbers. I thought that those were rounded off and not exact.
This is very disappointing.MevsEinstein said:I'll give in. The data represents the change from one composite number that has a unit digit of 7 to another one.
Absolutely, @MevsEinstein you need to take more care.jbriggs444 said:1. No, the data in #1 is not consistent with this pattern. In particular, 97 is not composite.
Absolutely, @MevsEinstein if you suspected a periodic relationship you should have calculated more values.jbriggs444 said:2. The sequence you describe is not periodic.
Absolutely, @MevsEinstein I hope you have learned your lesson here.jbriggs444 said:3. Seriously, dude. When asked what you are really trying to do, an answer is appropriate. Not prolonged evasion. We are 47 posts deep into an irrelevant tangent based on a misunderstanding that could have been corrected if you'd been forthcoming in response to @BvU in post #9.
Er... actually it will converge to ... 10, 10, 10, ... with a few 20's and 30's scattered in (we are looking at intervals between composites which become increasingly dense).jbriggs444 said:One would expect this sequence to converge to ... 30, 30, 30, 30, ... with a few 20, 10 and 10, 20 subsequences scattered therein.
jbriggs444 said:One would expect this sequence to converge to ... 30, 30, 30, 30, ... with a few 20, 10 and 10, 20 subsequences scattered therein.
Doesn’t throwing in a few other numbers mean that the sequence does not converge?pbuk said:Er... actually it will converge to ... 10, 10, 10, ... with a few 20's and 30's scattered in (we are looking at intervals between composites which become increasingly dense).
Strictly speaking, the data suggest a piecewise linear graph, which is somewhat different.phinds said:Your table is linear.
Right.phinds said:Of course, but the data does not support a pure straight line.