BUG #354 #362 ddof fix

README.md

@@ -113,7 +113,7 @@ $ pip install pandas_ta
 
 Latest Version
 --------------
-Best choice! Version: *0.3.14b*
+Best choice! Version: *0.3.15b*
 * Includes all fixes and updates between **pypi** and what is covered in this README.
 ```sh
 $ pip install -U git+https://github.com/twopirllc/pandas-ta
@@ -998,7 +998,9 @@ of the last bars defined by the length parameter. See ```help(ta.tos_stdevall)``
 * _Moving Average Convergence Divergence_ (**macd**): New argument ```asmode``` enables AS version of MACD. Default is False.  See ```help(ta.macd)```.
 * _Parabolic Stop and Reverse_ (**psar**): Bug fix and adjustment to match TradingView's ```sar```. New argument ```af0``` to initialize the Acceleration Factor. See ```help(ta.psar)```.
 * _Percentage Price Oscillator_ (**ppo**): Included new argument ```mamode``` as an option. Default is **sma** to match TA Lib. See ```help(ta.ppo)```.
+* _Standard Deviation_ (**stdev**): To use ```ddof``` argument, also set ```talib=False```. The ```ddof``` argument is not available if you have TA Lib installed in your environment. Same goes for **variance**. See ```help(ta.stdev)```.
 * _True Strength Index_ (**tsi**): Added ```signal``` with default ```13``` and Signal MA Mode ```mamode``` with default **ema** as arguments. See ```help(ta.tsi)```.
+* _Variance_ (**variance**): To use ```ddof``` argument, also set ```talib=False```. The ```ddof``` argument is not available if you have TA Lib installed in your environment. Same goes for **stdev**. See ```help(ta.variance)```.
 * _Volume Profile_ (**vp**): Calculation improvements. See [Pull Request #320](https://github.com/twopirllc/pandas-ta/pull/320) See ```help(ta.vp)```.
 * _Volume Weighted Moving Average_ (**vwma**): Fixed bug in DataFrame Extension call. See ```help(ta.vwma)```.
 * _Volume Weighted Average Price_ (**vwap**): Added a new parameter called ```anchor```. Default: "D" for "Daily". See [Timeseries Offset Aliases](https://pandas.pydata.org/pandas-docs/stable/user_guide/timeseries.html#timeseries-offset-aliases) for additional options. **Requires** the DataFrame index to be a DatetimeIndex. See ```help(ta.vwap)```.

pandas_ta/statistics/stdev.py

@@ -21,7 +21,7 @@ def stdev(close, length=None, ddof=None, talib=None, offset=None, **kwargs):
         from talib import STDDEV
         stdev = STDDEV(close, length)
     else:
-        stdev = variance(close=close, length=length, ddof=ddof).apply(npsqrt)
+        stdev = variance(close=close, length=length, ddof=ddof, talib=False).apply(npsqrt)
 
     # Offset
     if offset != 0:
@@ -56,9 +56,10 @@ Args:
     length (int): It's period. Default: 30
     ddof (int): Delta Degrees of Freedom.
                 The divisor used in calculations is N - ddof,
-                where N represents the number of elements. Default: 1
+                where N represents the number of elements. The 'talib' argument
+                must be false for 'ddof' to work. Default: 1
     talib (bool): If TA Lib is installed and talib is True, Returns the TA Lib
-        version. Default: True
+        version. TA Lib does not have a 'ddof' argument. Default: True
     offset (int): How many periods to offset the result. Default: 0
 
 Kwargs:

pandas_ta/statistics/variance.py

@@ -54,9 +54,10 @@ Args:
     length (int): It's period. Default: 30
     ddof (int): Delta Degrees of Freedom.
                 The divisor used in calculations is N - ddof,
-                where N represents the number of elements. Default: 0
+                where N represents the number of elements. The 'talib' argument
+                must be false for 'ddof' to work. Default: 1
     talib (bool): If TA Lib is installed and talib is True, Returns the TA Lib
-        version. Default: True
+        version. TA Lib does not have a 'ddof' argument. Default: True
     offset (int): How many periods to offset the result. Default: 0
 
 Kwargs:

setup.py

@@ -19,7 +19,7 @@ setup(
         "pandas_ta.volatility",
         "pandas_ta.volume"
     ],
-    version=".".join(("0", "3", "14b")),
+    version=".".join(("0", "3", "15b")),
     description=long_description,
     long_description=long_description,
     author="Kevin Johnson",