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SyncRNG
=======
A synchronized Tausworthe RNG usable in R and Python.


Why?
----

This program was created because it was desired to have the same random 
numbers in both R and Python programs. Although both languages implement a 
Mersenne-Twister RNG, the implementations are so different that it is not 
possible to get the same random numbers with the same seed.

SyncRNG is a Tausworthe RNG implemented in `syncrng.c`, and linked to both R 
and Python. Since both use the same underlying C code, the random numbers will 
be the same in both languages, provided the same seed is used.

How
---

First install the packages as stated under Installation. Then, in a Python 
script located in the same directory as `syncrng.so` and `SyncRNG.py`, you can 
do:

```python
from SyncRNG import SyncRNG

s = SyncRNG(seed=123456)
for i in range(10):
  print(s.randi())
```

Similarly, in an R script located in the same directory as `RSyncRNG.so` and 
`SyncRNG.R`, you can do:

```R
library(SyncRNG)

s = SyncRNG(seed=123456)
for (i in 1:10) {
	cat(s$randi(), '\n')
}
```

You'll notice that the random numbers are indeed the same.

Installation
------------

Installing the R package can be done through devtools:

```R
library(devtools)
devtools::install_github("GjjvdBurg/SyncRNG")
```

To install SyncRNG as a Python module, first clone the repository. The Python 
module can then be installed locally for the user using:

```sh
python setup.py install --user
```
or system-wide through:

```sh
sudo python setup.py install
```

Notes
-----

The random numbers are uniformly distributed on `[0, 2^32 - 1]`.


TODO
----

It may be easier to provide system-wide installation through an R package and 
a Python module.