Nbodyplot Class
*****************************************

This module provides the basic functions to plot the
simulation of a N-body problem. This module is based on `matplotlib`.

Build a `Nbodyplot` object
==========================


.. code-block:: python

   plt = nbodypy.Nbodyplot()


Here the documentation of the constructor.

.. automethod:: nbodypy.Nbodyplot.__init__

One can define multiple plots using the optional parameter `fig`.

Plot a solution
===============

Plot a  2 dimensional solution
------------------------------

.. automethod:: nbodypy.Nbodyplot.plotSol2D


Let us plot a 2 dimensional system (that is to say with a `dim`
parameter equal to two).

.. code-block:: python

   plt = nbodypy.Nbodyplot()
   zinit = numpy.array([0, 0.316046051487446, 0.864077674448677, 0,  0.100941149773621, -0.158023025743723, -0.432038837224337, 2.02906597904133, -0.100941149773621 , -0.158023025743723,  -0.43203883722434, -2.02906597904133])

   Eight = nbodypy.Nbody(N=3,init=zinit)
   t = numpy.linspace(0, 1.0/3, 100)
   plt.plotSol2D(Eight,t, mode="png",name="Eight")


This example produce a `png` file.

.. image:: ./images/Eight.png

The first parameter is an instance of the `Nbody` class, the second is
an `numpy.array` of times to plot the solution.

The `mode` parameter allows to choose the mode of representation. By
default, we have a popup window, produced by `matplotlib`, in which
the figure is plotted. We can choose `png` or `pdf` to produce
external file.

The `boundingbox` allows to chose the bounding box of the plot in the
local coordinates, by default (`None`), the bounding box is
automatically computed by `matplotlib`.

Plot a 3 dimensional solution
-----------------------------

.. automethod:: nbodypy.Nbodyplot.plotSol3D


.. code-block:: python

   plt = nbodypy.Nbodyplot()

   zinit = numpy.array([0.165649854848924,  3.0549363634996e-151 ,    0.209141794901608,
                     8.86909514289322e-29 ,     2.03225904939571, -9.31938237331704e-29,
                     -0.0828249274244622 ,    0.160070428973807,    -0.104570897450804,
                     -2.04906075007578 ,    -1.01612952469786 ,     1.15731474026243,
                     -0.0828249274244618 ,   -0.160070428973807 ,   -0.104570897450804,
                     2.04906075007578,     -1.01612952469785,     -1.15731474026243])

   Arotating = numpy.array([[0.0, 5.13873206001209, 0.0],
                         [-5.13873206001209, 0.0, 0.0],
                         [0.0,0.0, 0.0]])



   Rotating3D = nbodypy.Nbody(N=3, dim=6, init = zinit,rotating=Arotating)
   t = numpy.linspace(0, 1.0/3.0, 100)
   plt.grid = False
   plt.points = True
   plt.plotSol3D(Rotating,t,mode='png',name="Rotating")

This example produce the following picture.


.. image:: ./images/Rotating.png

The default parameter `projection` is equal to `True`. If we set it to
`False` then we obtain only the 3D view.



Plot a 4 dimensional solution
-----------------------------

.. automethod:: nbodypy.Nbodyplot.plotSol4D


.. code-block:: python

   plt = nbodypy.Nbodyplot()
   plt.points = True

   Ortho4D = nbodypy.Nbody(jsonFile="4DExample.json")
   t = numpy.linspace(0, 23.388651110001, 100)

   plt.plotSol4D(Ortho4D,t,mode='png',name="Ortho4D")

This example produce the following picture.


.. image:: ./images/Ortho4D.png

We can plot the solution using 2D projections. For that, we set the
parameter `projection` to `2d`.

.. code-block:: python

   plt = nbodypy.Nbodyplot()
   plt.points = True

   Ortho4D = nbodypy.Nbody(jsonFile="4DExample.json")
   t = numpy.linspace(0, 23.388651110001, 100)

   plt.plotSol4D(Ortho4D,t,mode='png',projection='2d',name="Ortho4D2d")

.. image:: ./images/Ortho4D2d.png


Make movies
===========

.. automethod:: nbodypy.Nbodyplot.CreateMovie2D

Here is an example of the use of this method.

.. code-block:: python

   plt = nbodypy.Nbodyplot()

   zinit = numpy.array([0, 0.316046051487446, 0.864077674448677, 0,  0.100941149773621, -0.158023025743723, -0.432038837224337, 2.02906597904133, -0.100941149773621 , -0.158023025743723,  -0.43203883722434, -2.02906597904133])

   Eight = nbodypy.Nbody(N=3,init=zinit)
   t = numpy.linspace(0, 1.0/3, 100)
   Eight.integrate(t,fileName="fileEight")
   plt.CreateMovie2D(Eight,1.0,200,prevTime=1.0/3, name="Eight",boundingbox=[-0.20,0.20,-0.4,0.4])


which produce a video numed `movieEight.mp4".

You can produce other types of images such as `svg`, `jpg`, `pdf`, but
the movie creation is only possible with the `png` mode. To create a
video, you have to install the `aconv` software (avaliable on linux
at least).

The `CreateMovie2D` method use the following intern method:

.. automethod:: nbodypy.Nbodyplot.imageMovie2D



Parameters for the plots
========================

There is two parameters:

- the `grid` one with the `True` default value and that allows to draw
  a grid behind the trajectories or not.
- The `points` parameter with the `True` default value and that allows
  to draw bullets to mark the bodies.