# [Numpy-discussion] solving linear equations

Hanno Klemm klemm@phys.ethz...
Fri Mar 9 03:35:18 CST 2012

```Hi,

have a look at scipy optimize. For a solution with only positive values you could consider using scipy.optimize.nnls, if you want more general (linear) constraints, have a look at the linear programming functions.

Another possibility would be looking at openOpt, which has probably more general solvers.

On Mar 9, 2012, at 7:33, salahudeen razac wrote:

>
> I wrote a script to solve the equation ‘P =Kd .V2 + Kl.VA.BT + C’ . To solve the equation I have used the matrix method.
>
>
> Ie, K*X = P          where
>
> [P] = [             P1
>
>                                 P2                                           a column matrix with the total powers P1, P2,P3…….PN at (V1,T1),(V2,T2)……(VN.TN) respectively,\
>
>                         P3
>
>                                 ..
>
>                                 PN  ]
>
>
>
>                                     [K] = [            V12      V1A.BT1    1
>
>                                                             V22      V2A.BT2    1
>
>                                                             V32      V3A.BT3    1
>
>                                                             ………………………..
>
>                                                             VN2      VNA.BTN    1 ]
>
>
>
>                                     [X]= [ Kd                           A column matrix with the unknowns
>
>                                                                 Kl
>
>                                                                 C  ]
>
>
> Now in order to solve multiply both sides with KT, ie             KT.K.X = KTP or A.X = B where A= KT.K and B= KTP
>
>
>
> Now we will get the matrix X by using linalg.solve(A,B) function which will eventually solve for a set of linear equations of the form Ax=B
>
>
>
> I was able to get the solution. But it is not acceptable since some of the values are negative. SO I want to know is there any way to give some constraints like the solution should contain only positive values and give any range for the solution?
>
>
>
> I also tried with linalg.lstsq and I am getting the same results
>
> -----
> Salahudeen razak | +917760902602
>
> o__
>  _> /__
> (_) \(_)... Burn fat not fuel
>
>
>
>
> _______________________________________________
> NumPy-Discussion mailing list
> NumPy-Discussion@scipy.org
> http://mail.scipy.org/mailman/listinfo/numpy-discussion

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.scipy.org/pipermail/numpy-discussion/attachments/20120309/c77c341d/attachment.html
```

More information about the NumPy-Discussion mailing list