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## rsgenpoly

 From: Robert T. Short Subject: rsgenpoly Date: Wed, 29 Aug 2018 17:04:36 -0700 User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1

Before I file a bug report and spend the time to fix this, let me make sure that I am not misinterpreting the results.  This is regarding rsgenpoly from the communications package.
```
rsgenpoly returns the following from MATLAB:

>> rsgenpoly(31,15)

ans = GF(2^5) array. Primitive polynomial = D^5+D^2+1 (37 decimal)

Array elements =

```
1   15   28    1   13    8    2   24   25   20   16   15 29   15   21    3   14
```

>> g = rsgenpoly(7,3)

g = GF(2^3) array. Primitive polynomial = D^3+D+1 (11 decimal)

Array elements =

1   3   1   2   3

octave yields

>> rsgenpoly(31,15)
ans =

Columns 1 through 9:

```
1.0000e+00   2.5700e+02   3.0245e+04   2.1606e+06 1.0470e+08   3.6442e+09   9.4065e+10   1.8334e+12   2.7211e+13
```
Columns 10 through 17:

```
3.0784e+14   2.6387e+15   1.6904e+16   7.9057e+16 2.5977e+17   5.6242e+17   7.1149e+17   3.9190e+17
```
>> rsgenpoly(7,3)
ans =

1    15    80   180   144

```
This is very recent version of MATLAB - either the most recent or the one just before.  I have octave 4.0.3 with communications 1.2.1.  I do not install the comm packages or any dependencies because there are too many conflicts with my own library functions, so I just cherry pick what I need and install the bits.
```
```
I am pretty sure this is an error and the offending line is a convolution that does the arithmetic on the integers instead the appropriate Galois field, but I would appreciation some feedback. If it is an error I will fix it.  Shouldn't be hard.
```
DB

```