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Thread Subject:
exp function

Subject: exp function

From: mshahrashoub shahrashoub

Date: 9 Sep, 2010 09:04:08

Message: 1 of 8

Hi,

I want to ask a question about exponentiation, i hope somebody can help me.

If I have a small values like x= 0.0014 and y = 0.0074 . how can i use exp.
As you can see in above " Y" 5 times bigger than "X" . But when I use exp
Values ll change like 1.0014 and 1.0074. So they are getting closer ? I want to increase the distance , not decrease. Does anybody know how to do?

thanks in advance

Subject: exp function

From: Ross W

Date: 9 Sep, 2010 10:59:24

Message: 2 of 8

" mshahrashoub shahrashoub" <shahrashoub@yahoo.com> wrote in message <i6a7u8$s0g$1@fred.mathworks.com>...
> Hi,
>
> I want to ask a question about exponentiation, i hope somebody can help me.
>
> If I have a small values like x= 0.0014 and y = 0.0074 . how can i use exp.
> As you can see in above " Y" 5 times bigger than "X" . But when I use exp
> Values ll change like 1.0014 and 1.0074. So they are getting closer ? I want to increase the distance , not decrease. Does anybody know how to do?
>
> thanks in advance

Hi

for x near zero, exp(x) is approximately 1+x

it's not clear what you want, but how about the square root?
>> [ y x y^.5 x^.5 y^.5-x^.5 ]

ans =

    0.0074 0.0014 0.0860 0.0374 0.0486

Ross

Subject: exp function

From: mshahrashoub shahrashoub

Date: 9 Sep, 2010 12:00:22

Message: 3 of 8

thanks Ross ,for your reply

square root helps but not too much. Do you know any kind of quadratic or etc function to get this numbers bigger and distance also will get bigger

For example when I use exp (1) result 2.7183
                               and exp(3) result 20.0855
at the beginning second number 3 times bigger than first number but when I use exp
function it is 10 times bigger than before.

I want to get this with small numbers(when the value close to 0)

like 0.0014 and 0.0074

Thanks in advance

Subject: exp function

From: Jan Simon

Date: 9 Sep, 2010 12:31:18

Message: 4 of 8

Dear mshahrashoub shahrashoub,

you have two small numbers and want to get them bigger, while the distance is getting bigger also?
Mutliply them by 37.

Kind regards, Jan

Subject: exp function

From: mshahrashoub shahrashoub

Date: 9 Sep, 2010 12:46:07

Message: 5 of 8

"Jan Simon" <matlab.THIS_YEAR@nMINUSsimon.de> wrote in message <i6ak2m$mrh$1@fred.mathworks.com>...
> Dear mshahrashoub shahrashoub,
>
> you have two small numbers and want to get them bigger, while the distance is getting bigger also?
> Mutliply them by 37.
>
> Kind regards, Jan

Dear Jan,

It is working, May I ask why 37 rather than 47 or 100. What makes it special

Subject: exp function

From: Jan Simon

Date: 9 Sep, 2010 13:29:09

Message: 6 of 8

Dear mshahrashoub shahrashoub,

> > you have two small numbers and want to get them bigger, while the distance is getting bigger also?
> > Mutliply them by 37.

> It is working, May I ask why 37 rather than 47 or 100. What makes it special.

37 is based on an article in Scientific American concerning so called intelligence tests. In such tests there are often questions like "please find the following element of the sequence 1, 2, 4, 9, 16, x".
While a lot of people waste their time and energy in finding out, that the elements of this sequence "are" the squares of the natural numbers, the author stated that you can append 19 to every sequence of numbers, because there is always a polynomial, which has the desired numbers and 19 afterwards as roots. Finding this polynomial is a simple task for really intelligent persons, while searching for other answers, which *seems* to match the data, is a more mechanistic method.
Finally he was asked, why he did not use 17 or 4. He answered, that this has psychological reasons: Of course it would be a good idea to choose the favourite number. But often intelligence tests are performed during job interviews or qualifying exams. Then some psychologists try to analyse the choice of the favourite number: "Oh, look, he took the -1!", "Well, there is surely a reason that she likes 6" etc. This is not the right level for intelligent persons. Choose 19 to stop such nonsense.

Now, I did not advice to choose the 19 today, because I've applied an 2N-1 operator. A kind of breaking the symmetry.

My final advice: Do *not* use 100.

Jan

Subject: exp function

From: Jan Simon

Date: 9 Sep, 2010 13:50:32

Message: 7 of 8

Dear mshahrashoub shahrashoub,

I've found the author of the theorem: Carl E. Linderholm:
"Each sequence of natural number can be continued by 19."

Jan

Subject: exp function

From: mshahrashoub shahrashoub

Date: 9 Sep, 2010 14:35:31

Message: 8 of 8

"Jan Simon" <matlab.THIS_YEAR@nMINUSsimon.de> wrote in message <i6aon8$jc$1@fred.mathworks.com>...
> Dear mshahrashoub shahrashoub,
>
> I've found the author of the theorem: Carl E. Linderholm:
> "Each sequence of natural number can be continued by 19."
>
> Jan

Dear Jan,

Thank you for your reply, I will find it and read it :).
Sounds interesting.

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