Exercise 8: Wine

The goal of this exercise is to learn to perform a basic data analysis on real data using NumPy.

The data set that will be used for this exercise is the red wine data set.

How to tell if a given 2D array has null columns?

Using genfromtxt load the data and reduce the size of the numpy array by optimizing the types. The sum of absolute differences between the original data set and the "memory" optimized one has to be smaller than 1.10**-3. I suggest to use np.float32. Check that the numpy array weights 76800 bytes.
Print 2nd, 7th and 12th rows as a two dimensional array
Is there any wine with a percentage of alcohol greater than 20% ? Return True or False
What is the average % of alcohol on all wines in the data set ? If needed, drop np.nan values
Compute the minimum, the maximum, the 25th percentile, the 50th percentile, the 75th percentile, the median (50th percentile) of the pH
Compute the average quality of the wines having the 20% least sulphates
Compute the mean of all variables for wines having the best quality. Same question for the wines having the worst quality