Merge pull request #210 from icecube/seyfert_fix

Add `IrregularParameterGrid` class

skyllh/core/parameters.py

@@ -1346,6 +1346,189 @@ def round_to_upper_grid_point(self, value):
         return gp
 
 
+class IrregularParameterGrid(object):
+    """This class provides a data holder for a parameter that has a set of
+    discrete values on a grid. Thus, the parameter has a value grid.
+    This class represents a one-dimensional irregular grid.
+    """
+    @staticmethod
+    def from_BinningDefinition(binning):
+        """Creates a IrregularParameterGrid instance from a BinningDefinition instance.
+
+        Parameters
+        ----------
+        binning : BinningDefinition instance
+            The BinningDefinition instance that should be used to create the
+            ParameterGrid instance from.
+
+        Returns
+        -------
+        param_grid : instance of ParameterGrid
+            The created ParameterGrid instance.
+        """
+        return IrregularParameterGrid(
+            name=binning.name,
+            grid=binning.binedges,
+        )
+
+    def __init__(self, name, grid):
+        """Creates a new parameter grid.
+
+        Parameters
+        ----------
+        name : str
+            The name of the parameter.
+        grid : sequence of float
+            The sequence of float values defining the discrete grid values of
+            the parameter.
+        """
+        self.name = name
+        self.grid = grid
+
+    def __str__(self):
+        """Pretty string representation.
+        """
+        return '{:s} = {:s}'.format(
+            self._name, str(self._grid))
+
+    @property
+    def name(self):
+        """The name of the parameter.
+        """
+        return self._name
+
+    @name.setter
+    def name(self, name):
+        if not isinstance(name, str):
+            raise TypeError(
+                'The name property must be of type str!')
+        self._name = name
+
+    @property
+    def grid(self):
+        """The numpy.ndarray with the grid values of the parameter.
+        """
+        return self._grid
+
+    @grid.setter
+    def grid(self, arr):
+        if not issequence(arr):
+            raise TypeError(
+                'The grid property must be a sequence!')
+        if not isinstance(arr, np.ndarray):
+            arr = np.array(arr, dtype=np.float64)
+        if arr.ndim != 1:
+            raise ValueError(
+                'The grid property must be a 1D numpy.ndarray!')
+        self._grid = arr
+
+    @property
+    def ndim(self):
+        """The dimensionality of the parameter grid.
+        """
+        return self._grid.ndim
+
+    def add_extra_lower_and_upper_bin(self):
+        """Adds an extra lower and upper bin to this parameter grid. This is
+        usefull when interpolation or gradient methods require an extra bin on
+        each side of the grid.
+        """
+        newgrid = np.empty((self._grid.size+2,))
+        newgrid[1:-1] = self._grid
+        newgrid[0] = newgrid[1] - (newgrid[2] - newgrid[1])
+        newgrid[-1] = newgrid[-2] + (newgrid[-2] - newgrid[-3])
+        del self._grid
+        self.grid = newgrid
+
+    def copy(self):
+        """Copies this IrregularParameterGrid object and returns the copy.
+        """
+        copy = deepcopy(self)
+        return copy
+
+    def round_to_nearest_grid_point(self, value):
+        """Rounds the given value to the nearest grid point.
+
+        Note: If the given value is precisely in between two nearest grid
+        points, the lower nearest grid point will be returned!
+
+        Parameters
+        ----------
+        value : float | ndarray of float
+            The value(s) to round.
+
+        Returns
+        -------
+        grid_point : float | ndarray of float
+            The calculated grid point(s).
+        """
+        scalar_input = np.isscalar(value)
+
+        grid_middle = (self.grid[1:] + self.grid[:-1])/2
+        idx = np.searchsorted(grid_middle, value, side='left')
+        gp = self.grid[idx]
+
+
+        if scalar_input:
+            return gp.item()
+
+        return gp
+
+    def round_to_lower_grid_point(self, value):
+        """Rounds the given value to the nearest grid point that is lower than
+        the given value.
+
+        Note: If the given value is a grid point, that grid point will be
+              returned!
+
+        Parameters
+        ----------
+        value : float | ndarray of float
+            The value(s) to round.
+
+        Returns
+        -------
+        grid_point : float | ndarray of float
+            The calculated grid point(s).
+        """
+        scalar_input = np.isscalar(value)
+
+        idx = np.searchsorted(self.grid, value, side='right') - 1
+        gp = self.grid[idx]
+
+        if scalar_input:
+            return gp.item()
+
+        return gp
+
+    def round_to_upper_grid_point(self, value):
+        """Rounds the given value to the nearest grid point that is larger than
+        the given value.
+
+        Note: If the given value is a grid point, the next grid point will be
+              returned!
+
+        Parameters
+        ----------
+        value : float | ndarray of float
+            The value(s) to round.
+
+        Returns
+        -------
+        grid_point : ndarray of float
+            The calculated grid point(s).
+        """
+        scalar_input = np.isscalar(value)
+
+        idx = np.searchsorted(self.grid, value, side='right')
+        gp = self.grid[idx]
+
+        if scalar_input:
+            return gp.item()
+
+        return gp
+
+
 class ParameterGridSet(
         NamedObjectCollection):
     """Describes a set of parameter grids.
@@ -1364,7 +1547,7 @@ def __init__(
         """
         super().__init__(
             objs=param_grids,
-            obj_type=ParameterGrid,
+            obj_type=type(param_grids[0]),
             **kwargs)
 
     @property