Fix the calculation of XAS spectra with bins number or bins width

XAS.py

@@ -102,7 +102,8 @@ def xas(nrun, bins=None, Iokey='SCS_XGM', Itkey='MCP3apd', nrjkey='nrj', Iooffse
 
         Inputs:
             nrun: xarray of SCS data
-            bins: array of bin-edges or number of desired bins
+            bins: an array of bin-edges or an integer number of
+                desired bins or a float for the desired bin width.
             Iokey: string for the Io fields, typically 'SCS_XGM'
             Itkey: string for the It fields, typically 'MCP3apd'
             NRJkey: string for the nrj fields, typically 'nrj'
@@ -140,6 +141,12 @@ def xas(nrun, bins=None, Iokey='SCS_XGM', Itkey='MCP3apd', nrjkey='nrj', Iooffse
         num_bins = 80
         energy_limits = [np.min(nrj), np.max(nrj)]
         bins = np.linspace(energy_limits[0], energy_limits[1], num_bins+1)
+    elif type(bins) == int:
+        energy_limits = [np.min(nrj), np.max(nrj)]
+        bins = np.linspace(energy_limits[0], energy_limits[1], bins+1)
+    elif type(bins) == float:
+        energy_limits = [np.min(nrj), np.max(nrj)]
+        bins = np.arange(energy_limits[0], energy_limits[1], bins)
         
     dummy, nosample = binning(rundata['nrj'], rundata, whichIo, bins)
     muA = nosample['muA']