diff --git a/Makefile b/Makefile
index e6c0a97..6475b0d 100644
--- a/Makefile
+++ b/Makefile
@@ -3,6 +3,7 @@ LINT_TARGET_DIRS := PyEMD doc example
 init:
 	python -m venv .venv
 	.venv/bin/pip install -r requirements.txt
+	.venv/bin/pip install -e .[dev]
 	@echo "Run 'source .venv/bin/activate' to activate the virtual environment"
 
 test:
@@ -17,6 +18,7 @@ doc:
 
 format:
 	python -m black $(LINT_TARGET_DIRS)
+	python -m isort PyEMD
 
 lint-check:
 	python -m isort --check PyEMD
diff --git a/PyEMD/EMD.py b/PyEMD/EMD.py
index d52305d..1d7e58f 100644
--- a/PyEMD/EMD.py
+++ b/PyEMD/EMD.py
@@ -13,7 +13,7 @@
 from scipy.interpolate import interp1d
 
 from PyEMD.splines import akima, cubic, cubic_hermite, cubic_spline_3pts, pchip
-from PyEMD.utils import get_timeline, deduce_common_type
+from PyEMD.utils import deduce_common_type, get_timeline
 
 FindExtremaOutput = Tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray, np.ndarray]
 
@@ -199,14 +199,14 @@ def prepare_points(
             Position (1st row) and values (2nd row) of maxima.
         """
         if self.extrema_detection == "parabol":
-            return self._prepare_points_parabol(T, S, max_pos, max_val, min_pos, min_val)
+            return self.prepare_points_parabol(T, S, max_pos, max_val, min_pos, min_val)
         elif self.extrema_detection == "simple":
-            return self._prepare_points_simple(T, S, max_pos, max_val, min_pos, min_val)
+            return self.prepare_points_simple(T, S, max_pos, max_val, min_pos, min_val)
         else:
             msg = "Incorrect extrema detection type. Please try: 'simple' or 'parabol'."
             raise ValueError(msg)
 
-    def _prepare_points_parabol(self, T, S, max_pos, max_val, min_pos, min_val) -> Tuple[np.ndarray, np.ndarray]:
+    def prepare_points_parabol(self, T, S, max_pos, max_val, min_pos, min_val) -> Tuple[np.ndarray, np.ndarray]:
         """
         Performs mirroring on signal which extrema do not necessarily
         belong on the position array.
@@ -324,7 +324,7 @@ def _prepare_points_parabol(self, T, S, max_pos, max_val, min_pos, min_val) -> T
 
         return max_extrema, min_extrema
 
-    def _prepare_points_simple(
+    def prepare_points_simple(
         self,
         T: np.ndarray,
         S: np.ndarray,
diff --git a/PyEMD/tests/test_utils.py b/PyEMD/tests/test_utils.py
index f90a56b..e766ff2 100644
--- a/PyEMD/tests/test_utils.py
+++ b/PyEMD/tests/test_utils.py
@@ -2,7 +2,7 @@
 
 import numpy as np
 
-from PyEMD.utils import get_timeline, deduce_common_type
+from PyEMD.utils import deduce_common_type, get_timeline
 
 
 class MyTestCase(unittest.TestCase):
@@ -37,5 +37,6 @@ def test_deduce_common_types(self):
         self.assertEqual(deduce_common_type(np.int32, np.int32), np.int32)
         self.assertEqual(deduce_common_type(np.float32, np.float64), np.float64)
 
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/PyEMD/tests/test_visualization.py b/PyEMD/tests/test_visualization.py
index 882e6b6..982f9b3 100644
--- a/PyEMD/tests/test_visualization.py
+++ b/PyEMD/tests/test_visualization.py
@@ -19,8 +19,8 @@ def test_instantiation2(self):
         emd.emd(S, t)
         imfs, res = emd.get_imfs_and_residue()
         vis = Visualisation(emd)
-        self.assertTrue(np.alltrue(vis.imfs == imfs))
-        self.assertTrue(np.alltrue(vis.residue == res))
+        self.assertTrue(np.all(vis.imfs == imfs))
+        self.assertTrue(np.all(vis.residue == res))
 
     def test_check_imfs(self):
         vis = Visualisation()
@@ -40,7 +40,7 @@ def test_check_imfs3(self):
 
         out_imfs, out_res = vis._check_imfs(imfs, None, False)
 
-        self.assertTrue(np.alltrue(imfs == out_imfs))
+        self.assertTrue(np.all(imfs == out_imfs))
         self.assertIsNone(out_res)
 
     def test_check_imfs4(self):
@@ -57,8 +57,8 @@ def test_check_imfs5(self):
         imfs, res = emd.get_imfs_and_residue()
         vis = Visualisation(emd)
         imfs2, res2 = vis._check_imfs(imfs, res, False)
-        self.assertTrue(np.alltrue(imfs == imfs2))
-        self.assertTrue(np.alltrue(res == res2))
+        self.assertTrue(np.all(imfs == imfs2))
+        self.assertTrue(np.all(res == res2))
 
     def test_plot_imfs(self):
         vis = Visualisation()
diff --git a/PyEMD/utils.py b/PyEMD/utils.py
index 5dc9657..9dd71be 100644
--- a/PyEMD/utils.py
+++ b/PyEMD/utils.py
@@ -1,5 +1,5 @@
-from typing import Optional
 from functools import cache
+from typing import Optional
 
 import numpy as np
 
@@ -52,13 +52,13 @@ def smallest_inclusive_dtype(ref_dtype: np.dtype, ref_value) -> np.dtype:
 
     raise ValueError("Unsupported dtype '{}'. Only intX and floatX are supported.".format(ref_dtype))
 
+
 @cache
 def deduce_common_type(xtype: np.dtype, ytype: np.dtype) -> np.dtype:
     if xtype == ytype:
         return xtype
-    if np.version.version[0] == '1':
+    if np.version.version[0] == "1":
         dtype = np.find_common_type([xtype, ytype], [])
     else:
         dtype = np.promote_types(xtype, ytype)
     return dtype
-    
\ No newline at end of file