Fixing #102 - check for zero residue and discard

PyEMD/EMD.py

@@ -822,6 +822,7 @@ def emd(self, S: np.ndarray, T: Optional[np.ndarray] = None, max_imf: int = -1)
 
         # Create arrays
         imfNo = 0
+        extNo = -1
         IMF = np.empty((imfNo, N))  # Numpy container for IMF
         finished = False
 
@@ -911,11 +912,17 @@ def emd(self, S: np.ndarray, T: Optional[np.ndarray] = None, max_imf: int = -1)
                 finished = True
                 break
 
-        # Saving residuum
-        self.residue = residue = S - np.sum(IMF, axis=0)
+        # If the last sifting had 2 or less extrema then that's a trend (residue)
+        if extNo <= 2:
+            IMF = IMF[:-1]
+
+        # Saving imfs and residue for external references
         self.imfs = IMF.copy()
-        if not np.allclose(residue, 0):
-            IMF = np.vstack((IMF, residue))
+        self.residue = S - np.sum(self.imfs, axis=0)
+
+        # If residue isn't 0 then add it to the output
+        if not np.allclose(self.residue, 0):
+            IMF = np.vstack((IMF, self.residue))
 
         return IMF
 

PyEMD/__init__.py

@@ -1,6 +1,6 @@
 import logging
 
-__version__ = "1.0.0"
+__version__ = "1.1.0"
 logger = logging.getLogger("pyemd")
 
 from PyEMD.EMD import EMD

requirements.txt

@@ -1,4 +1,3 @@
-numpy>=1.12
-numpydoc
-scipy>=0.19
+numpy>=1.12,<=1.20
+scipy>=0.19,<=1.18
 pathos>=0.2.1

setup.py

@@ -1,6 +1,6 @@
 from setuptools import find_packages, setup
 
-VERSION = "1.0.1"
+VERSION = "1.1.0"
 
 DESCRIPTION = "Implementation of the Empirical Mode Decomposition (EMD) and its variations"