pip optional dependencies

Sometimes you want to make your python package usable for different situations, e.g. flask or bottle or django. If You want to minimize dependencies You can use an optional dependency in setup.py: extras_require={ ‘flask’: [‘Flask>=0.8’, ‘blinker>=1.1’] } Now you can install the library with: pip install raven[flask]  

Add Vaadin Maven Archetype to IntelliJ

On Windows You can add the Maven archetype for Vaadin to IntelliJ IDEA the following way: Open: c:\Users\username\.IdeaIC2017.3\system\Maven\Indices\UserArchetypes.xml and add the line: <archetypes> <archetype groupId=”com.vaadin” artifactId=”vaadin-archetype-application” version=”8.3.2″ /> </archetypes Now you can create a new Vaadin project via Maven  

Numpy linspace function

To create e.g. x-axis indices you can use the linspace function from numpy. You give it a range (e.g. 0 to 23) and the number of divisions and it will distribute the values evenly across that range. The stop values is included in the resulting value array by default. Example: import numpy as np np.linspace(0,…

Data Science Overview

Questions Data Science tries to answer one of the following questions: Classification -> “Is it A or B?” Clustering -> “Are there groups which belong together?” Regression -> “How will it develop in the future?” Association -> “What is happening very often together?” There are two ways to tackle these problem domains with machine learning:…

Removing pyc files on server

Sometimes Python gives You a hard time when You deploy code to a server after you changed directory structures or simply moved files. With the following command You can remove the pyc files in the working directory and subdirectories: find . -name \*.pyc -delete

SQL – the dark side

Sometimes your RDBMS does not allow you to do certain changes like updating a table without using a WHERE clause that uses a key column. When you are really sure what you want to do: SET SQL_SAFE_UPDATES = 0; Now the dirty brown magic can begin! Back to the SQL-Tutorial