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## #1 2018-01-28 14:11:20

MrGiggles
Member
Registered: 2018-01-28
Posts: 2

### Pattern Problem

Hi everyone,

I am not sure how to title this problem (If anyone can help with title)

Here it is

The signal came down from X to Y (Fig 1) If the signal came up it will be vice versa Y to X so we keep XY as an example.
We now are at point Y now there are two outcomes it will reach point A or Point B
A=Y+1.5
B=Y-0.5
Between the A( y+1.5)and B( y-0.5), the signal can fluctuate

E.g. It can go to Y+ 1,1.3,1.4,0.7,0.5 etc and then go for to Y-0.5
Or
It can go to Y- 0.1,0.2,0.4,0.4 and then go to Y+1.5

It can fluctuate in between y+1.5 and Y-0.5 in a randomly till it reaches A or B.

Our goal is to follow signal A or B with minimum error keeping it mind the fluctuation which can occur between -0.5 and 1.5 in any combination it is random.point Y we have to choose correct point A or B but at point Y we don't know which one will it be so we need to pick the right point A or B and we can afford an error of 0.5 in the process

An error of 0.5 is acceptable if we can have lower than that will be ideal
Or
The simplest and best possible formula to follow the signal with minimum error

Best,
Harry

Last edited by MrGiggles (2018-01-28 14:53:31)

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## #2 2018-01-28 21:23:21

bob bundy
Registered: 2010-06-20
Posts: 8,228

### Re: Pattern Problem

hi MrGiggles

Welcome to the forum.

I'm not sure I can help as I'm a bit confused about the problem.  (no diagram seen)

Here's what I think you're asking:

There's a line connection between point X and point Y.  Then the signal can either be sent to A, or to B.  Either is acceptable if the signal stays within 0.5 of the original from X ( not higher nor lower than this limit)

There's no loss between X and Y (or it's irrelevant since we have to use this connection).

If A is chosen the signal will go up to value at Y + 1.5
If B is chosen the signal will drop to value at Y - 0.5

In addition transmission along YA and YB are subject to fluctuations as follows A route: minus 0.1,0.2,0.4,0.4    B route: plus  1,1.3,1.4,0.7,0.5

Is this correct so far?

Are these fluctuations the only ones possible?  And is each equally likely?

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2018-01-28 21:55:16

MrGiggles
Member
Registered: 2018-01-28
Posts: 2

### Re: Pattern Problem

Hi Bob,

Thank you for the welcome.

https://imgur.com/FVn5gqJ

This is Fig I hope this helps.

The loss between XY is insignificant

Yes let assume length of X=150 and Y=0 and the signal will be sent either to A (150) or B (-50)  and at point Y we have to choose if the signal will be sent to A or B now in process to reach the correct signal we can change our direction but the maximum Loss/error in transmission can be -50

Rest all you are correct Bob

Thank you.

Last edited by MrGiggles (2018-01-28 22:02:39)

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## #4 2018-01-29 02:55:49

bob bundy
Registered: 2010-06-20
Posts: 8,228

### Re: Pattern Problem

I think this can be done by calculating expected result for each route.

Assuming the plus and minus figures are equally likely:

the expected result for A is - (0.25 x 0.1 + 0.25 x 0.2 + 0.25 x 0.4 + 0.25 x 0.4)  In your post you have 0.4 twice.  If that is a typo then just substitute the correct value instead. = - 0.25 x (0.1+0.2+0.4+0.4) = 0.25 x 1.1 = - 0.275

And for B = + 0.2 x 1 + 0.2 x 1.3 + 0.2 x 1.4 + 0.2 x 0.7 + 0.2 x 0.5 = 0.2 x (1+1.3+1.4+0.7+0.5) = 0.2 x 4.9 = + 0.98

So for A = Y + 1.5 - 0.275 = Y + 1.225

and for B = Y - 0.5 + 1.225 = Y + 0.725

Neither has an expected result within the limits.  Am I misunderstanding something here?

Bob

formula for an expected result is

where the Ps are the probabilities and the Ws are the 'weights' for each possibility.

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #5 2018-01-29 07:43:53

bob bundy
Registered: 2010-06-20
Posts: 8,228

### Re: Pattern Problem

I've received your message but I don't understand what you're wanting.  I've visited the contest page and seen this:

"Contest Brief

Please find the problem attached to the file below."

But I cannot find any such attachment.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #6 2018-01-30 20:55:02

bob bundy
Registered: 2010-06-20
Posts: 8,228

### Re: Pattern Problem

Today I visited your link page again and found someone calling themselves "Mohammad Matin" has copied my earlier post and submitted it as their entry.  This seems to be doubly dishonest: (1) because it was not that person's work; and (2) it claimed to be a solution but definitely was not!.

It's a great shame that the work of members on this forum is being abused in this way.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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