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## Re: Error installing the symbol package

 From: Doug Stewart Subject: Re: Error installing the symbol package Date: Sat, 6 May 2017 10:56:10 -0400

On Sat, May 6, 2017 at 10:36 AM, Simon A. Turner wrote:

Hello Doug

I am looking for numerical answers, I was led to believe that I needed this plugin to solve a simultaneous equation input with less effort than converting my equations to a matrix. Either way the problem of the plug in not installing remains for quite a few people as a quick google search reveals.

Kind regards

Simon

if you have 2 loops

--------------      r1  -------------------------------------r3---------------- vout
|                                                  |                                     |
Vin                    i1                         r2                     i2           r4
|                                                  |                                     |
___________________________________________________

i1*r1 + i1* r2  - i2*r2                                    =Vin
-i1*r2             + i2*r2 +i2*r3  + i2*r4            =0

vout=i2*r4

let
r1=1
r2=2
r3=3 ohms
r4=4
Vin =5 volts

then we have
i1                       i2
r1+r2              -r2                                         = 5
-r2                  + r2 +r3 +r4                           =0

a=[ 3    -2;
-2   9]
b=[5
0]

cur=a\b

vout=cur(2)*4

octave gives:

>> a=[ 3    -2;
-2   9]
a =

3  -2
-2   9

>> b=[5
0]
b =

5
0

>>
>> cur=a\b
cur =

1.95652
0.43478

>>
>> vout=cur(2)*4
vout =  1.7391 volts

I hope this helps  :-)