RE: Button Help Example

• To: mathgroup at smc.vnet.net
• Subject: [mg81260] RE: [mg81238] Button Help Example
• From: "%uvt_fullname%" <>
• Date: Tue, 18 Sep 2007 00:33:40 -0400 (EDT)
• References: <200709170734.DAA15516@smc.vnet.net>

```Dear All,

I am facing the following problem:

1) I have a system of m=12 linear equations, with n=11 variables.

2) I want to identify those linearly dependent equations and drop them from
the system to have a solution.

3) I applied the following code (somebody from MathGroup provided this last
year), which is the Gram-Schmidt method of orthogonalization:

Clear[V];

equ = {i - 0.4 p == 0, k - 0.16 z == 0, m - 0.9 p == 0, c - 0.83 r == 0, x -
0.7 p ==0, p + m - i - c - k - x == 0, y - p + i == 0,
s - r + c == 0, b - m + x == 0, y - r == 0, k - s - b == 0,
z - p - m == 0};

{h1, V} = CoefficientArrays[equ, {p, m, i, k, x, c, y, r, s, b, z}];

Do[Do[If[V[[n]] != {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, V[[m]] =
(V[[n]].V[[n]]) V[[m]] - (V[[n]].V[[m]]) V[[n]]], {n, 1, m - 1}], {m, 2,
12}]

Map[If[# != {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, "keep", "discard"] &, V]

This Code always indicates the 6th row to be discarded no matter which order
you input the equations in "equ".

Isn't there a problem with this code or maybe I am missing something.

Your help is appreciated...

Tugrul

```

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