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Started by Martin Dick
Sat, 20 Jun 1998 00:00
Complex numbers. Help!
Author: Martin Dick
Date: Sat, 20 Jun 1998 00:00
Date: Sat, 20 Jun 1998 00:00
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Hello. I am in need of an explanation of the theory of complex numbers and their uses. I have consulted several textbooks tending to this subject but they are all far too advanced for my case. I also need an explanation of how complex numbers relate to fractal images as fractals are a useful aid in artificial intelligence decision making. This sort of research can allow computers to make decisions of their own by relating fractal`s infinite complexity to the organised tree like formation of computer databases. This enables _logical_ decision making and re-inforces artificial common sense. Uses of this type of system could include helping the disabled by letting the computer perform operations with less strenuous user input and the idea of computers making decisions in dangerous situations where humans are too slow to think (nuclear power plants, hospitals, etc,) - this could save a lot of lives. Thanks. -- E-mail: torbain@globalnet.co.uk
Re: Complex numbers. Help!
Author: Robert Baer
Date: Sun, 21 Jun 1998 00:00
Date: Sun, 21 Jun 1998 00:00
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Martin Dick wrote:
>
> Hello. I am in need of an explanation of the theory of complex numbers and
> their uses. I have consulted several textbooks tending to this subject but
> they are all far too advanced for my case.
>
> I also need an explanation of how complex numbers relate to fractal images
> as fractals are a useful aid in artificial intelligence decision making.
> This sort of research can allow computers to make decisions of their own by
> relating fractal`s infinite complexity to the organised tree like formation
> of computer databases. This enables _logical_ decision making and
> re-inforces artificial common sense.
>
> Uses of this type of system could include helping the disabled by letting
> the computer perform operations with less strenuous user input and the idea
> of computers making decisions in dangerous situations where humans are too
> slow to think (nuclear power plants, hospitals, etc,) - this could save a
> lot of lives. Thanks.
>
> --
> E-mail:
> torbain@globalnet.co.uk
Start with a good book in electronics covering AC theory.
imaginary
^
| /
| /
| /
|/ angle
-------------------------+--------------------> real
|
|
|
|
First, think of simple cartesian coordinates where a point can be
expressed in terms of distance in X and Y. An alternate way of
describing the same place is in polar coordinates; angle and distance
from reference.
Now think of AC power to a component, and use the voltage as a
reference (reference phase or zero phase). Then let that component be a
capacitor and measure the current thru it; it will be out of phase in
relation to the voltage. Since a capacitor opposes a change in voltage,
the current will "lead" or be ahead of the voltage in phase by 90
degrees (for a perfect capacitor, and most are quite close to this).
So now you see the angle part; the distance is related to the amount
of current.
In electronics, this relationship is expressed as a complex number for
calculation purposes, hence the reference.
The above is like a drop of water; get the book or books and get wet!
Re: Complex numbers. Help!
Author: Jim Berwick
Date: Sun, 21 Jun 1998 00:00
Date: Sun, 21 Jun 1998 00:00
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We help people with problems here, not people who want a college degree. Martin Dick wrote: > Hello. I am in need of an explanation of the theory of complex numbers and > their uses. I have consulted several textbooks tending to this subject but > they are all far too advanced for my case. > > I also need an explanation of how complex numbers relate to fractal images > as fractals are a useful aid in artificial intelligence decision making. > This sort of research can allow computers to make decisions of their own by > relating fractal`s infinite complexity to the organised tree like formation > of computer databases. This enables _logical_ decision making and > re-inforces artificial common sense. > > Uses of this type of system could include helping the disabled by letting > the computer perform operations with less strenuous user input and the idea > of computers making decisions in dangerous situations where humans are too > slow to think (nuclear power plants, hospitals, etc,) - this could save a > lot of lives. Thanks. > > -- > E-mail: > torbain@globalnet.co.uk -- Jim Berwick Visit my page at http://members.xoom.com/Hyper_Hands/ Now updated by the 4th of every month, complete with new pictures of hot people. Check it out! And be sure to give me FEED BACK! Reply by removing nospam from my e-mail address.
Re: Complex numbers. Help!
Author: Reg Edwards
Date: Tue, 23 Jun 1998 00:00
Date: Tue, 23 Jun 1998 00:00
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Its quite simple really. A complex number is of the form x + jy where j is the squareroot of minus 1. Don't let j put you off because you will never have to work out what it is. All you have to do is square it. So j squared is minus 1. It now becomes easy to multiply two complex numbers together as follows - (a + jb)*(c + jd) = ac - bd + j(bc + ad) which is just another complex number. Think of j as a radioactive tracer which allows the "imaginary" components to be kept track of in the course of a long calculation. And thats all there is to it - well almost. But it's all very easy. -- Reg G4FGQ http://www.btinternet.com/~g4fgq.regp
Re: Complex numbers. Help!
Author: glocock
Date: Tue, 23 Jun 1998 00:00
Date: Tue, 23 Jun 1998 00:00
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In article <01bd9f1d$19766760$8c2e63c3@default>, "Reg Edwards" <g4fgq.regp@btinternet.com> wrote: > > Its quite simple really. > > A complex number is of the form x + jy where j is the squareroot of minus > 1. > > Don't let j put you off because you will never have to work out what it is. > All you have to do is square it. > > So j squared is minus 1. > > It now becomes easy to multiply two complex numbers together as follows - > > (a + jb)*(c + jd) = ac - bd + j(bc + ad) which is just another complex > number. > > Think of j as a radioactive tracer which allows the "imaginary" components > to be kept track of in the course of a long calculation. > > And thats all there is to it - well almost. But it's all very easy. I don't know about it all being very easy, but here's the other standard results you need: (a + jb)+(c + jd) = (a+c)+j(b+d) (a + jb)/(c + jd) =(a+jb)*(c-jd)/(cc+dd) mod(a+jb)=sqrt(aa+bb) theta(a+jb)=atan(b/a) ....(but get the right quadrant) a+jb=mod(a+jb)*exp(j.theta) Their great advantage is that in exponential form (the last equation) you can manipulate 2 dimensional numbers in one expression. On a graph, you plot the real part on the x axis and the imaginary part on the y axis. -----== Posted via Deja News, The Leader in Internet Discussion ==----- http://www.dejanews.com/ Now offering spam-free web-based newsreading
Re: Complex numbers. Help!
Author: Reg Edwards
Date: Tue, 30 Jun 1998 00:00
Date: Tue, 30 Jun 1998 00:00
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j can also be considered as an operator on a vector. Multiplication by j rotates by 90 degrees. Multiplying twice by j rotates by 180 degrees - ie, in the opposite direction and hence the change in sign. ( j squared = -1)
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