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Misconfiguration of TypeScript

Once upon a time, after an update, TypeScript service stopped to run, so no Intellisense, no nothing.

The following steps where taken:

• updated global Node.js (see below);
• updated global TypeScript afterwards;
• deleted the .config/Code folder but preserving the User subfolder;
• started VSC afresh. A new, clean .config/Code folder was created;

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#!/usr/bin/env python3
# coding=UTF8
# -*- coding: utf-8 -*-

print("This is the Python3 shebang")

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Launch Anaconda in Linux

Default installation folder is ~/anaconda.

To launch it: ./anaconda-navigator &.

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Interpolating a Range with a Predefined Color Scale

const pointColorScale = d3
  .scaleSequential(d3.interpolateTurbo)
  .domain(extent);

where interpolateTurbo is the predefined color scale and extent is the variable min / max values.

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version: '3.5'

networks:
  sunnsaas:
    external: false
    name: network_name
    attachable: true

volumes:
  phd-data-postgis:

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#!/bin/bash

# Declare the array
folders=('Abacus' 'Bergamonte' 'Clemence' 'Dardanelles')

# Print all array
echo "The whole array: ${folders[@]}"
echo

# Print an element

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import * as rx from "rxjs";

/**

  An example on how to create an Observable in TypeScript.
  
*/
const observable: rx.Observable<number> =
  new rx.Observable<number>((o: rx.Subscriber<number>) => {

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PostGIS Recipes

Some miscellanea PostGIS recipes.

Resetting the GEOMETRY Type and SRID for a Table Column

This is specially useful when creating tables with CREATE TABLE AS SELECT because columns types are not correctly set at database metadata and therefore public.geometry_columns can guess the geometry type and SRID of newly created GEOMETRY columns. After creating the table, run:

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PostgreSQL: Trigger Examples

A simple trigger that preprocess the insert or updated rows before inserting them. Modifies input data inside the target table.

First, create a PL/PgSQL function that returns a trigger. In this function, NEW refers to the new data entering the table, while OLD refers to the old data in case there were any:

create or replace function public.fn__urban_limit_preprocessing()
returns trigger as
$$

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PostgreSQL Custom Aggregates: Weighted Average Example

In this example we are going to create a custom aggregate function for PostgreSQL. Remember that an aggregate function is the kind of functions that works over a group or set of rows to produce a computation based on an accumulative process that iterates over the set of rows, with an alternative final process over the computated accumulative. For example, take this set of data:

val	wei	grp
2	4	a
4	3	a
5	10	b
8	15	b