Docs (#81)

* clean `condition` module
* add docs

pina/plotter.py

@@ -1,14 +1,9 @@
 """ Module for plotting. """
-import matplotlib
-# matplotlib.use('Qt5Agg')
 import matplotlib.pyplot as plt
 import numpy as np
 import torch
 
 from pina import LabelTensor
-from pina import PINN
-from .problem import SpatialProblem, TimeDependentProblem
-#from pina.tdproblem1d import TimeDepProblem1D
 
 
 class Plotter:
@@ -20,11 +15,14 @@ class Plotter:
         """
             Plot a sample of solution.
 
-        :param pinn: the PINN object.
-        :type pinn: PINN
-        :param variables: pinn variable domains: spatial or temporal,
-            defaults to None.
-        :type variables: str, optional
+        :param PINN pinn: the PINN object.
+        :param list(str) variables: variables to plot. If None, all variables
+            are plotted. If 'spatial', only spatial variables are plotted. If
+            'temporal', only temporal variables are plotted. Defaults to None.
+
+        .. todo::
+            - Add support for 3D plots.
+            - Fix support for more complex problems.
 
         :Example:
             >>> plotter = Plotter()
@@ -134,24 +132,22 @@ class Plotter:
     def plot(self, pinn, components=None, fixed_variables={}, method='contourf',
              res=256, filename=None, **kwargs):
         """
-            Plot sample of PINN output.
+        Plot sample of PINN output.
 
-        :param pinn: the PINN object.
-        :type pinn: PINN
-        :param components: function components to plot, defaults to None.
-        :type components: list['str'], optional
-        :param fixed_variables: function variables to be kept fixed during
-            plotting passed as a dict where the dict-key is the variable
-            and the dict-value is the value to be kept fixed, defaults to {}.
-        :type fixed_variables: dict, optional
-        :param method: matplotlib method to plot the solution,
-            defaults to 'contourf'.
-        :type method: str, optional
-        :param res: number of points used for plotting in each axis,
-            defaults to 256.
-        :type res: int, optional
-        :param filename: file name to save the plot, defaults to None
-        :type filename: str, optional
+        :param PINN pinn: the PINN object.
+        :param list(str) components: the output variable to plot. If None, all
+            the output variables of the problem are selected. Default value is
+            None.
+        :param dict fixed_variables: a dictionary with all the variables that
+            should be kept fixed during the plot. The keys of the dictionary
+            are the variables name whereas the values are the corresponding
+            values of the variables. Defaults is `dict()`.
+        :param {'contourf', 'pcolor'} method: the matplotlib method to use for
+            plotting the solution. Default is 'contourf'.
+        :param int res: the resolution, aka the number of points used for
+            plotting in each axis. Default is 256.
+        :param str filename: the file name to save the plot. If None, the plot
+            is shown using the setted matplotlib frontend. Default is None.
         """
         if components is None:
             components = [pinn.problem.output_variables]
@@ -192,14 +188,12 @@ class Plotter:
 
     def plot_loss(self, pinn, label=None, log_scale=True):
         """
-            Plot the loss function values during traininig.
+        Plot the loss function values during traininig.
 
-        :param pinn: the PINN object.
-        :type pinn: PINN
-        :param label: matplolib label, defaults to None
-        :type label: str, optional
-        :param log_scale: use of log scale in plotting, defaults to True.
-        :type log_scale: bool, optional
+        :param PINN pinn: the PINN object.
+        :param str label: the label to use in the legend, defaults to None.
+        :param bool log_scale: If True, the y axis is in log scale. Default is
+            True.
         """
 
         if not label: