egnor

DW3000 "missing manual" notes

Overall

The DW3000 is an exciting part, available as a convenient Arduino-shield eval board with good distribution. HOWEVER, this is NOT a "maker friendly" part with SparkFun or Adafruit type tutorials and examples! It is a sophisticated radio that can be the heart of a positioning system, but you have to do quite a lot of heavy lifting to get there.

For basic use, the older-but-still-good DW1000 may be a better choice; interface libraries are available for Arduino and Raspberry Pi. Or look into packaged location-system vendors, like Estimote, Pozyx, Ubitrack and many others

kgjenkins

The following Python code will, every 30 seconds, automatically update the data from the source for any QGIS layer with 'autoUpdate' in the layer name. Each time it updates, it will put the timestamp in the layer name, although you could leave that part out.

This is particularly useful for remote data sources like json-over-http or even local CSV files that might be changed by another program while the QGIS project is open.

Just paste the code into the QGIS Python console.

import threading
import datetime

nitheeshkl

Using GigE cam as webcam for Zoom/Skype/Teams

TL;DR: Creates a Gstreamer pipeline to read camera frames from a GigE camera, using Aravis library, and publish them as V4l2 camera source, using V4l2loopback, that can be read by video conferencing programs like Zoom/Skype/Teams.

gst-launch-1.0 aravissrc blocksize=5013504 h-binning=1 v-binning=1 ! video/x-bayer,format=rggb,framerate=100/5,width=2448,height=2048 ! bayer2rgb ! video/x-raw,format=RGBx ! videoconvert ! video/x-raw,format=YUY2 !  aspectratiocrop aspect-ratio=16/9 ! videoscale ! video/x-raw,width=1280,height=720 ! queue ! v4l2sink device=/dev/video0

---

The Basics

dtrugman

/*
 * Copyright (c) 2020-present Daniel Trugman
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *

narate

Create a Wi-Fi hotspot on Linux using nmcli

Original post : https://unix.stackexchange.com/a/310699

nmcli con add type wifi ifname wlan0 con-name Hostspot autoconnect yes ssid Hostspot
nmcli con modify Hostspot 802-11-wireless.mode ap 802-11-wireless.band bg ipv4.method shared
nmcli con modify Hostspot wifi-sec.key-mgmt wpa-psk
nmcli con modify Hostspot wifi-sec.psk "veryveryhardpassword1234"

kunaltyagi

template <class ...Args>
bool scalar_compare(YAML::Node&, YAML::Node&);
template<class T, class ...Args>
bool helper_compare(YAML::Node& node1, YAML::Node& node2)
{
    try
    {
        return node1.as<T>() == node2.as<T>();
    }
    catch(YAML::TypedBadConversion<T>& e)

rmtsrc

SSH authentication via U2F

Enabling SSH U2F authentication.

After some research online I've found a patch to the OpenSSH server that enables U2F authentication.

However there are 2 major caveats that would stop me from using this in a production environment:

• Security - the patch for OpenSSH has not yet been accepted/merged and currently works on an older version of OpenSSH
• Currently doesn't work on Mac OS, though maybe possible once Homebrew/legacy-homebrew#43676 is resolved

arjunvenkat

How to seed a Rails database with a CSV file

1. Setup

First, Create a folder inside of lib called seeds

Put your CSV file example.csv into the lib/seeds folder. In the example below, the file is called real_estate_transactions.csv

Make sure you've created a resource with the appropriate columns to match your seed data. The names don't have to match up.

gitaarik

Git Submodules basic explanation

Why submodules?

In Git you can add a submodule to a repository. This is basically a repository embedded in your main repository. This can be very useful. A couple of usecases of submodules:

• Separate big codebases into multiple repositories.

DanGe42

#include <ucontext.h>
#include <sys/types.h>
#include <sys/time.h>
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <poll.h>

/* ucontext sample program