Add extended gaussian

Just for convenience
raymondEhlers · Aug 20, 2019 · af69d29 · af69d29
1 parent 2277444
commit af69d29
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Showing 2 changed files with 18 additions and 1 deletion.
diff --git a/pachyderm/fit/__init__.py b/pachyderm/fit/__init__.py
@@ -17,4 +17,4 @@
 from .cost_function import (  # noqa: F401
     BinnedChiSquared, BinnedLogLikelihood, ChiSquared, CostFunctionBase, LogLikelihood, SimultaneousFit
 )
-from .function import AddPDF, gaussian  # noqa: F401
+from .function import AddPDF, extended_gaussian, gaussian  # noqa: F401
diff --git a/pachyderm/fit/function.py b/pachyderm/fit/function.py
@@ -73,3 +73,20 @@ def gaussian(x: Union[np.ndarray, float], mean: float, sigma: float) -> Union[np
         Calculated gaussian value(s).
     """
     return 1.0 / np.sqrt(2 * np.pi * np.square(sigma)) * np.exp(-1.0 / 2.0 * np.square((x - mean) / sigma))
+
+def extended_gaussian(x: Union[np.ndarray, float], mean: float, sigma: float, amplitude: float) -> Union[np.ndarray, float]:
+    r""" Extended gaussian.
+
+    .. math::
+
+        f = A / \sqrt{2 * \pi * \sigma^{2}} * \exp{-\frac{(x - \mu)^{2}}{(2 * \sigma^{2}}}
+
+    Args:
+        x: Value(s) where the gaussian should be evaluated.
+        mean: Mean of the gaussian distribution.
+        sigma: Width of the gaussian distribution.
+        amplitude: Amplitude of the gaussian.
+    Returns:
+        Calculated gaussian value(s).
+    """
+    return amplitude / np.sqrt(2 * np.pi * np.square(sigma)) * np.exp(-1.0 / 2.0 * np.square((x - mean) / sigma))