refactor calcSparsingAndNumPoints to avoid use of unset availableNpnts

1 files changed, 17 insertions, 2 deletions

diff --git a/qolab/hardware/scope/_basic.py b/qolab/hardware/scope/_basic.py
index c0a6f13..e67e6af 100644
--- a/qolab/hardware/scope/_basic.py
+++ b/qolab/hardware/scope/_basic.py
@@ -10,9 +10,24 @@ from qolab.data.trace import TraceSetSameX
 
 
 def calcSparsingAndNumPoints(self, availableNpnts=None, maxRequiredPoints=None):
+    """Calculate sparcing and number of sparced points.
+    
+    Parameters
+    ----------
+    availableNpnts: int or None
+        Number of available points. If set to None exit with error
+    maxRequiredPoints: int or (None)
+        number of requested points after decimation.
+        If availableNpnts< maxRequiredPoints*2,
+        decimation is impossible and we will get up to factor of 2 more
+        than requested.
+
+    Return
+    ------
+    (sparsing, Npnts, availableNpnts, maxRequiredPoints)
+    """
     if availableNpnts is None:
-        # using channel 1 to get availableNpnts
-        availableNpnts = self.getAvailableNumberOfPoints(1)
+        raise ValueError("Invalid availableNpnts value, must be int.")
     if maxRequiredPoints is None:
         maxRequiredPoints = self.maxRequiredPoints