change(retained): default cutoff is 0

src/agora/io/signal.py

@@ -101,9 +101,7 @@ class Signal(BridgeH5):
                 )
                 return 300
 
-    def retained(
-        self, signal, cutoff=global_parameters.signal_retained_cutoff
-    ):
+    def retained(self, signal, cutoff=0):
         """Get retained cells for a Signal or list of Signals."""
         if isinstance(signal, str):
             # get data frame

src/aliby/global_parameters.py

@@ -36,6 +36,3 @@ fluorescence_functions = [
     "imBackground",
     "max5px_median",
 ]
-
-# default fraction of time a cell must be in the experiment to be kept by Signal
-signal_retained_cutoff = 0.8