ENH #163 Adding Price Volume indicator, missing file

pandas_ta/volume/pvr.py

@@ -0,0 +1,53 @@
+# -*- coding: utf-8 -*-
+from pandas_ta.momentum import roc
+from pandas_ta.utils import get_offset, signed_series, verify_series
+from numpy import nan as npNaN
+from pandas import Series
+
+
+def pvr(close, volume):
+    """ Indicator: Price Volume Rank"""
+    # Validate arguments
+    close = verify_series(close)
+    volume = verify_series(volume)
+    
+    # Calculate Result
+    close_diff = close.diff().fillna(0)
+    volume_diff = volume.diff().fillna(0)
+    pvr_ = Series(npNaN, index=close.index)
+    pvr_.loc[(close_diff >= 0) & (volume_diff >= 0)] = 1
+    pvr_.loc[(close_diff >= 0) & (volume_diff < 0)] = 2
+    pvr_.loc[(close_diff < 0) & (volume_diff >= 0)] = 3
+    pvr_.loc[(close_diff < 0) & (volume_diff < 0)] = 4
+
+    # Name and Categorize it
+    pvr_.name = f"PVR"
+    pvr_.category = "volume"
+
+    return pvr_
+
+pvr.__doc__ = \
+"""Price Volume Rank
+
+The Price Volume Rank was developed as a simple indicator that could be calculated even without a computer. The basic interpretation is to buy when the PV Rank is below 2.5 and sell when it is above 2.5.
+The Price Volume Rank was developed by Anthony J. Macek and is described in his article in the June, 19994 issue of Technical Analysis of Stocks & Commodities magazine.
+
+Sources:
+    https://www.fmlabs.com/reference/default.htm?url=PVrank.htm
+
+Calculation:
+    if 'close change' >= 0 and 'volume change' >= 0
+        return 1
+    if 'close change' >= 0 and 'volume change' < 0
+        return 2
+    if 'close change' < 0 and 'volume change' >= 0
+        return 3
+    if 'close change' < 0 and 'volume change' < 0
+        return 4
+Args:
+    close (pd.Series): Series of 'close's
+    volume (pd.Series): Series of 'volume's
+    
+Returns:
+    pd.Series: New feature generated.
+"""