[Tutor] toy program to find standard deviation of 2 columns of a sqlite3 database

[Manprit Singh]

Dear Sir,

My target is still to do this task in pure python. without using an
iterable.
Just shown you using pandas, how easy it is in the last mail . There are
several easy ways also. I will come up with a solution given by Dennis Lee
bieber.


I am exploring other options also, The one using numpy was also explored by
me as given below:

import sqlite3
import numpy as np

conn = sqlite3.connect(":memory:")
cur = conn.cursor()
cur.execute("create table table1(X1, X2)")
lst = [(2, 5),
         (4, 3),
         (5, 2),
         (7, 1)]
cur.executemany("insert into table1 values(?, ?)", lst)
cur.execute("select * from table1")
print(np.std(cur.fetchall(), axis=0))

array([1.80277564, 1.47901995])  which is the right answer

For column names :
col_names= [cur.description[i][0] for i in (0, 1)]
print(col_names)

['X1', 'X2']




My target is still to do this task in pure python. with out using an
iterable