Tux Machines

Python, PostgreSQL, and Bash

Posted by Roy Schestowitz on May 23, 2023

Cumulative Percentage Pandas

The “cumsum()” and “sum()” functions of the “pandas” library are implemented in Python to find the cumulative percentages.

NumPy Gradient Method

To calculate the gradient of the function or Numpy “N-Dimensional” array the “numpy.gradient()” method is utilized in Python.

PostgreSQL Group by Day (Date)

Tutorial on how to group the dates per day when working with PostgreSQL using the DATE_TRUNC and the DATE_PART functions along with practical examples.

PostgreSQL Group By Examples

Guide on different examples of working with the GROUP BY clause to form groups of rows from single or multiple columns when working with the SELEC statement.

PostgreSQL Escape the Single Quote in String

How to escape the single quotes to use it within a string by doubling the single quotes or using the E backslash method or the dollar-quoted string method.

PostgreSQL Group by Hour (Time)

Guide on how to group the timestamp columns using the EXTRACT and DATE_TRUNC functions and how to use the aggregate functions with group by hour in PostgreSQL.

Using the =~ Operator in Bash

Comprehensive tutorial on the various methods of using the =~ operator in Bash to search the string values with different types of regular expressions.

Escape a Single Quote in Bash

The purposes of using the single quotes in the Bash script using single quotes with both echo and printf commands to define a string data or execute a command.

Bash Logical AND (&&) Operator

The simple uses of the logical AND operator in Bash script to define the logical expressions in any programming language and check two or more conditions.

Bash Substring after a Specified Character

Practical guide on the various uses of Bash substring extraction to extract the substring from a string data after a specified character using the Bash script.