Re: enquiry
- To: mathgroup at smc.vnet.net
- Subject: [mg89217] Re: enquiry
- From: dh <dh at metrohm.ch>
- Date: Thu, 29 May 2008 07:06:40 -0400 (EDT)
- References: <g1j6da$qlu$1@smc.vnet.net>
Hi Bico,
do not use funny names like y*, this only gives you troubles.
To solve your problem, first define a function of m and n that
calculates the matrix element: fun[m,n]. Then create the matrix. If your
indices start with 1 you can use Array, e.g.:
Array[fun,{2,3}]
There are other forms of Array for more complicated cases. But in this
case it may be easier to use Table:
Table[fun[m,n],{m,3,5},{n,2,3}]
hope this helps, Daniel
abubaker alshafee wrote:
> Hi All
>
> I am tryin to build a Matrix
> Vmn = Array[v, {m, n}] with V equal to
>
> V = (-(y* N[BesselK[13 I, 2 Pi n y*]]
> Exp[(13 Pi)/2]] Exp[2 Pi I n (((j - 1/2)/2)
> Q)] Exp[-2 Pi I m (((j - 1/2)/2) Q)]))
> (1/(2 Q)) + KroneckerDelta[m, n]
> (Sqrt[y] N[BesselK[13 I, 2 Pi m y]
> Exp[(13 Pi)/2]])
>
> I used the following but I faild to get the correct matrix or array,
> I got a reapeted answers , I also need to generate a loop to build the Array of V elements Any one can help with that,
> here the loops i wrote but it is not working
>
> MY = 10;
> For[m = 2, m <= MY, m++,
> Q = 11;
> b = {};
> y = 0.3;
> y* = 0.3;
> For[n = 2, n <= MY, n++,
> For[j = 1, j <= Q, j = j + 1,
> v = (Sqrt[y]*
> N[BesselK[13 I,2 Pi n y*]
> Exp[13 Pi/2)]
> Exp[2 Pi I n ((j - 1/2) Q/2)]
> Exp[2 Pi I m ((j - 1/2) Q/2)];
> v = KroneckerDelta[m, n] (Sqrt[y]
> N[BesselK[13 I, 2 Pi m y]
> E^((13 Pi)/2), 50]) -
> v/(2 Q);
> AppendTo[b, v];
>
> gg = Array[v, {m, n}]]]
> Print[gg]
>
>
>
>
> Regards
> Bico
--
Daniel Huber
Metrohm Ltd.
Oberdorfstr. 68
CH-9100 Herisau
Tel. +41 71 353 8585, Fax +41 71 353 8907
E-Mail:<mailto:dh at metrohm.com>
Internet:<http://www.metrohm.com>