feat: thin method added to Corr class which allows to thin out a

correlator in order suppress correlations between neighbouring entries

pyerrors/correlators.py

@@ -376,6 +376,24 @@ class Corr:
         """Reverse the time ordering of the Corr"""
         return Corr(self.content[:: -1])
 
+    def thin(self, spacing=2, offset=0):
+        """Thin out a correlator to suppress correlations
+
+        Parameters
+        ----------
+        spacing : int
+            Keep only every 'spacing'th entry of the correlator
+        offset : int
+            Offset the equal spacing
+        """
+        new_content = []
+        for t in range(self.T):
+            if (offset + t) % spacing != 0:
+                new_content.append(None)
+            else:
+                new_content.append(self.content[t])
+        return Corr(new_content)
+
     def correlate(self, partner):
         """Correlate the correlator with another correlator or Obs
 

tests/correlators_test.py

@@ -283,3 +283,11 @@ def test_hankel():
     corr.Hankel(2)
     corr.Hankel(6, periodic=True)
 
+
+def test_thin():
+    c = pe.Corr([pe.pseudo_Obs(i, .1, 'test') for i in range(10)])
+    c *= pe.cov_Obs(1., .1, '#ren')
+    thin = c.thin()
+    thin.fit(lambda a, x: a[0] * x)
+    c.thin(offset=1)
+    c.thin(3, offset=1)