exercise2():
  Get a datafile in text format from the class website.
  Read the data from the datafile.
  Print the first five lines.
  Compute some statistical measurements.
  Normalize the data, and recompute the statistics.
  When finished, delete the datafile.
  Already have a copy of faithful_data.txt

  "faithful_data.txt" contains 272 rows and 2 columns.

  First five lines of data:

  (0)         3.6        79
  (1)         1.8        54
  (2)         3.3        74
  (3)         2.3        62
  (4)         4.5        85

  Statistics for data:

  Minimum          1.6        43
  Maximum          5.1        96
  Range            3.5        53
  Mean             3.5        71
  Variance         1.3   1.8e+02
  STD              1.1        14
  RMS               43   8.4e+02
  Graphics saved as "exercise2.0.jpg"

  kmeans cluster centers:
[[ 0.70970327  0.67674488]
 [-1.26008539 -1.20156744]]
  Graphics saved as "exercise2.1.jpg"

  Deleting dataset file:

exercise2():
  Normal end of execution.