search for: tp3247566p3247592

Displaying 1 result from an estimated 1 matches for "tp3247566p3247592".

Did you mean: tp3247566p3247566
2011 Jan 30
3
How to do a moving window on standard deviation
I'd like to use vectorization to take a 4 point moving window on standard deviation on the close column and create another variable (st.dev) in the dataframe. Here's the dataframe head(xyz) Date Close 1 2011-01-28 56.42 2 2011-01-27 57.37 3 2011-01-26 56.48 4 2011-01-25 56.39 5 2011-01-24 55.74 6 2011-01-21 55.46 So the first 3 elements to the new st.dev column would be zero