Api extra (#166)

Changes to be able to run the example notebooks: 

- Invert gain map on setting (multiplication is faster but user supplies
ADU/energy)
- Cast after applying gain map not to loose precision (Important for
int32 clusters)
- "factor" for ClusterFileSink 
- Cluster size available to be able to create the right file sink

python/aare/ClusterFinder.py

@@ -1,5 +1,8 @@
 
 from ._aare import ClusterFinder_Cluster3x3i, ClusterFinder_Cluster2x2i, ClusterFinderMT_Cluster3x3i, ClusterFinderMT_Cluster2x2i, ClusterCollector_Cluster3x3i, ClusterCollector_Cluster2x2i
+
+
+from ._aare import ClusterFileSink_Cluster3x3i, ClusterFileSink_Cluster2x2i
 import numpy as np
 
 def ClusterFinder(image_size, cluster_size, n_sigma=5, dtype = np.int32, capacity = 1024):
@@ -48,3 +51,17 @@ def ClusterCollector(clusterfindermt, cluster_size = (3,3), dtype=np.int32):
         #TODO! add the other formats
         raise ValueError(f"Unsupported dtype: {dtype}. Only np.int32 is supported.")
 
+def ClusterFileSink(clusterfindermt, cluster_file, dtype=np.int32): 
+    """ 
+    Factory function to create a ClusterCollector object. Provides a cleaner syntax for 
+    the templated ClusterCollector in C++.
+    """
+
+    if dtype == np.int32 and clusterfindermt.cluster_size == (3,3): 
+        return ClusterFileSink_Cluster3x3i(clusterfindermt, cluster_file)
+    elif dtype == np.int32 and clusterfindermt.cluster_size == (2,2):
+        return ClusterFileSink_Cluster2x2i(clusterfindermt, cluster_file)
+     
+    else: 
+        #TODO! add the other formats
+        raise ValueError(f"Unsupported dtype: {dtype}. Only np.int32 is supported.")

python/aare/__init__.py

@@ -11,7 +11,7 @@ from ._aare import ROI
 
 # from ._aare import ClusterFinderMT, ClusterCollector, ClusterFileSink, ClusterVector_i
 
-from .ClusterFinder import ClusterFinder, ClusterCollector, ClusterFinderMT
+from .ClusterFinder import ClusterFinder, ClusterCollector, ClusterFinderMT, ClusterFileSink
 from .ClusterVector import ClusterVector