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MathGroup Archive 2012

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How to easily set up all coefficients to be positive in Solving an integer equation?

  • To: mathgroup at smc.vnet.net
  • Subject: [mg124304] How to easily set up all coefficients to be positive in Solving an integer equation?
  • From: Rex <aoirex at gmail.com>
  • Date: Mon, 16 Jan 2012 17:11:13 -0500 (EST)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com

Given a vector `A==[a_1, a_2, a_3,...,a_n]`, where a_i are integers,
now
solving an equation
`=E2=88=91a_i * x_i==0` with all x_i>==0, and x_i to be integers.

We can write some code like this
`Solve[A . Table[x[i], {i, n}] ==  0 && Table[x[i] > 0, {i, n}],
Integers]`

But the conditions above `Table[x[i] > 0` is not rightly coded. That
should be
`x[1]>0 && x[2]>0 && x[3]>0 &&...x[n]>0`
Is there any easy way to write such code?



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