Quickstart¶

This document oulitnes how to easily start using the TMgen tool.

Download and installation¶

Using pip¶

pip install tmgen

From source¶

Clone

git clone https://github.com/progwriter/tmgen

Install using pip in development mode
```
cd tmgen
pip install -e .
```

Example usage¶

TMgen defines a TrafficMatrix object that is returned by all generator functions. Internally it contains a 3-d numpy array which contains volume of traffic between origin-destination pairs for different time epochs. For TM models that do not have a time component, the third dimension is of size 1.

Quick overview on how to use them is given here, for full details please see the TMgen API

Generating a traffic matrix¶

Lets generate a uniform traffic matrix for a network with 3 nodes:

>>> from tmgen.models import uniform_tm
>>> tm = uniform_tm(3, 100, 300)
>>> print(tm) 
array([[[...

...

...]]])

This gives us a 3x3x1 array with values between 100 and 300 — volume for each node pair, with only one time epoch.

Accessing tm entries¶

TMgen gives you a number of ways to access the TM values. Lets generate an exponential TM with the mean volume of 500 and 2 time epochs.

>>> from tmgen.models import exp_tm
>>> tm = exp_tm(3, 500, 2)

Accessing the matrix attrbute gives us the underlying Numpy array:

>>> tm.matrix 
array([[[...

...

...]]])

Also we can request a traffic matrix at a specific epoch (0-indexed):

>>> tm.at_time(1) 
array([[...]])

Or the values between any node pair, with a particular aggregation metric:

>>> tm.between(0,2,'all') 
array([...])
>>> tm.between(0,2,'max') 
>>> tm.between(0,2,'mean') 

See TMgen API for all supported functions.

Saving/Loading a traffic matrix¶

TMs can be easily loaded using the python-native pickle format:

>>> from tmgen import TrafficMatrix
>>> tm.to_pickle('mytm')
>>> tm = TrafficMatrix.from_pickle('mytm')