Calculate speed

- [Instructor] We now have a function…that can calculate distances…and we also have time information.…That's all the information we need to calculate speed.…Let's ask why calculating…the distances between all the points.…In regular Python, we'll use a follow.…But in Pandas, and in scientific Python in general,…we try not to use follow ups…since they are slower than using Vector operations.…Since we're using NumPy U functions circle_dist…it means we can use it on hall erase.…However, we need pairs of points.…

And for that we're going to use the shift method.…Let's see an example.…So S a pd.series of np.arange of five.…Then if you look at S,…it's from zero to four.…Now let's try.…s.shift…Everything is shifted down.…We can also shift up.…s.shift minus one…and now everything is shifted up.…How does shift help us?…Dist equal circle dist of df.latitude…and df.longitude…and then df.latitude again,…this time shifted.…

And again .shift.…And let's see the first 10 values.…We see that the first value is nan,…not a number.…Since we have nan at the start of latitude and longitude.…