[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 556

 
MetaDriver:

Alsu, correct me if I'm being obtuse.

sX = x0 + x1rn

dX = x0 - x1rn

sX+dX = x0+x1rn+x0-x1rn = 2*x0

after normalisation we get x0 again

)))

 
alsu:

sX = x0 + x1rn

dX = x0 - x1rn

sX+dX = x0+x1rn+x0-x1rn = 2*x0

after normalization we get x0 again

)))

Right, missed the sum and difference normalisation in the interval.

sX = x0 + x1rn

dX = x0 - x1rn

sX->sXn; dX-> dXn;

sXn+dXn = x0+x1rn+x0-x1rn = 2*x0 = X1

after normalizing (dividing by the square root of 2) we get x1 :)

 
MetaDriver:

......... It's a bit more complicated, it doesn't work that easy. After obtaining xi vector at each step, one should first "add-subtract-normalize" it with the next input vector and so on until the input vectors are exhausted. Something like this.

Seems to be correct. There is a degenerate case when at any of the steps we obtain a vector equal to the next one. It is unlikely, but it exists. Then we just repeat the process from the beginning and that's it.
 
Svinotavr:
MetaDriver, alsu, sorry for interrupting the 'orthogonal vector set' discussion.

On your knees !!!

;)

 
MetaDriver:

Well yes, missed the sum and difference normalisation in the interval.

sX = x0 + x1rn

dX = x0 - x1rn

sX->sXn; dX-> dXn;

sXn+dXn = x0+x1rn+x0-x1rn = 2*x0 = X1

After normalizing (dividing by the root of 2) we get x1 = what we need. :)

still does not work

Example

x0 = (1/sqrt(2), 1/sqrt(2)), x1rn = (-1/sqrt(2), 1/(sqrt(2))

sX = (0, sqrt(2)), sXn = (0,1)

dX = x1rn-x0 = (sqrt(2), 0), dXn = (1,0)

sXn+dXn = (1,1) - this vector is orthogonal to neither x0 nor x1

although both were initially orthogonal))) but we can give an example without this

I'm asleep already)))) It's working out, of course)))

 
alsu:

still doesn't work

Example

x0 = (1/sqrt(2), 1/sqrt(2)), x1rn = (-1/sqrt(2), 1/(sqrt(2))

sX = (0, sqrt(2)), sXn = (0,1)

dX = x1rn-x0 = (sqrt(2), 0), dXn = (1,0)

sXn+dXn = (1,1) - this vector is not orthogonal to either x0 or x1

although both were orthogonal initially)))) but you can give an example without that

not true. it is orthogonal. :) the result after normalization is equal to the first vector, and as you correctly noted - it is orthogonal to the second. :)

OK, go to sleep now. )))

 
MetaDriver:

Not true, it is orthogonal. :) the result after normalisation is equal to the first vector and, as you correctly pointed out, it is orthogonal to the second. :)

OK, go to sleep now. )))


It still doesn't work shit, those just worked out because I originally took a couple of orthogonal ones:

Example

x1rn = (0.6, 0.8), x0 = (1, 0)

it's an approximation, but you can see everything.


 
i.e. the normalised sum and difference are orthogonal to each other, but in general will not be directed to the initial vectors at 45 degrees, and hence their sum will not be orthogonal to them.
 
alsu:

It still doesn't work, those just worked out because I initially took a pair of orthogonal ones:

Example

x1rn = (0.6, 0.8), x0 = (1, 0)

figure is approximate, but everything is visible

Tex. Looks like you are right. The solution is close, but the formula has to be corrected.

After calculating sX and dX, we don't need to normalise them, but exchange their modules. i.e. we calculate |sX| and |dX|,

and then transform sXtr = sX*|dX|/|sX| ; dXtr = dX*|sX|/|dX|

Then they can then be added together and expanded with the correct output result.

No? Again ???

 
MetaDriver:

After calculating sX and dX, we do not need to normalise them, but exchange their modules. i.e. we calculate |sX| and |dX|,

and then transform sXtr = sX*|dX|/|sX| ; dXtr = dX*|sX|/|dX|

Then they can then be added together and expanded with the correct output result.

It goes something like this:

Here a=x0, b=x1rn