add relativity

Author: RobTillaart

libraries/relativity/.arduino-ci.yml

@@ -0,0 +1,7 @@
+compile:
+  # Choosing to run compilation tests on 2 different Arduino platforms
+  platforms:
+    - uno
+    - leonardo
+    - due
+    - zero

libraries/relativity/.github/workflows/arduino-lint.yml

@@ -0,0 +1,13 @@
+
+name: Arduino-lint
+
+on: [push, pull_request]
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: arduino/arduino-lint-action@v1
+        with:
+          library-manager: update
+          compliance: strict

libraries/relativity/.github/workflows/arduino_test_runner.yml

@@ -0,0 +1,13 @@
+---
+name: Arduino CI
+
+on: [push, pull_request]
+
+jobs:
+  arduino_ci:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: Arduino-CI/action@master
+          #   Arduino-CI/[email protected]

libraries/relativity/.github/workflows/jsoncheck.yml

@@ -0,0 +1,18 @@
+name: JSON check
+
+on:
+  push:
+    paths:
+      - '**.json'
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: json-syntax-check
+        uses: limitusus/json-syntax-check@v1
+        with:
+          pattern: "\\.json$"
+

libraries/relativity/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021-2021 Rob Tillaart
+
+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:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

libraries/relativity/README.md

@@ -0,0 +1,67 @@
+
+[![Arduino CI](https://github.com/RobTillaart/relativity/workflows/Arduino%20CI/badge.svg)](https://github.com/marketplace/actions/arduino_ci)
+[![License: MIT](https://img.shields.io/badge/license-MIT-green.svg)](https://github.com/RobTillaart/relativity/blob/master/LICENSE)
+[![GitHub release](https://img.shields.io/github/release/RobTillaart/relativity.svg?maxAge=3600)](https://github.com/RobTillaart/relativity/releases)
+
+
+# relativity
+
+Arduino library with relativity functions.
+
+
+## Description
+
+This experimental library implements a number of functions that give indication of the time dilation etc due to relativistic speed.
+
+Goal: Educational purposes or when one puts a cubesat into space :)
+
+
+## Interface
+
+- **relativity()** constructor
+- **double getC()** returns speed of light
+- **double getG()** returns gravitational constant
+- **double factor(double speed)** returns sqrt(1-v2/c2)
+- **double gamma(double speed)** returns 1/sqrt(1-v2/c2)
+- **double relativeTime(double time, double speed)** returns the relative time for given time and speed.
+- **double relativeLength(double length, double speed)** returns the relative length for given length and speed.
+- **double relativeMass(double mass, double speed)** returns the relative mass for given mass and speed.
+- **double EnergyMass(double mass, double speed)** returns the energyMass for given mass and speed. Think E = mc^2.
+
+
+### Caching variants
+
+These functions are the same however the math to calculate a given factor and gamma is done only once and cached. So these function will perform a bit better, especially if floating point is slow.
+
+- **void setSpeed(double speed = 0)** set the speed once and calculate the factor and gamma to minimize math for next functions. Think caching.
+- **double getSpeed()** returns speed set.
+- **double getFactor()** returns factor for speed set
+- **double getGamma()** returns gamma for speed set.
+- **double relativeTime(double time)** returns the relative time for speed set with **setSpeed()**.
+- **double relativeLength(double length)** returns the relative length for speed set.
+- **double relativeMass(double mass)** returns the relative mass for speed set.
+- **double EnergyMass(double mass)** returns the energy mass for for speed set.
+
+
+### Gravity effects
+
+- **double gravitationalTime(double time, double speed)** returns time dilation due to gravitational effects.
+- **double diameterEarth(uint8_t longitude = 45)** calculates the diameter of the Earth given it is not a nice circle but more an ellipse, flatter on the poles and thicker on the equator.
+Longitude is in (absolute) degrees.
+- **double getPlanetMass(uint8_t n)** returns planet mass in kg where 0 = Sun, 1 = Mercury etc
+- **double getPlanetRadius(uint8_t n)** returns planet radius in kg where 0 = Sun, 1 = Mercury etc
+
+
+## Operations
+
+See examples for typical usage.
+
+
+## Future
+
+- test test test test
+- add more functions
+- fix some overflow conditions.
+  
+- add moons?
+- add caching version of mass / radius;

libraries/relativity/examples/gamma_table/gamma_table.ino

@@ -0,0 +1,49 @@
+//
+//    FILE: gamma_table.ino
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.0
+// PURPOSE: test formulas
+//    DATE: 2021-05-29
+//     URL: https://github.com/RobTillaart/relativity
+
+
+#include "relativity.h"
+
+
+uint32_t start, stop;
+
+relativity R;
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+
+  Serial.print("\nSpeed of light (m/s):\t");
+  Serial.println(R.getC());
+
+  Serial.println("\n Percentage\t Speed\t\t factor\t\t gamma\n");
+
+  for (double perc = 1; perc < 99.9999; perc += (100 - perc) / 10)
+  {
+    double v = R.getC() * perc * 0.01;
+
+    Serial.print(" ");
+    Serial.print(perc, 5);
+    Serial.print("\t ");
+    Serial.print(v * 0.001);
+    Serial.print("\t ");
+    Serial.print(R.factor(v), 6);
+    Serial.print("\t ");
+    Serial.print(R.gamma(v ), 6);
+    Serial.println();
+  }
+  Serial.println("done...");
+}
+
+
+void loop()
+{
+}
+
+// -- END OF FILE --

libraries/relativity/examples/gravity_demo/gravity_demo.ino

@@ -0,0 +1,38 @@
+//
+//    FILE: gravity_demo.ino
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.0
+// PURPOSE: test formulas
+//    DATE: 2021-05-29
+//     URL: https://github.com/RobTillaart/relativity
+
+
+#include "relativity.h"
+
+relativity R;
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+
+  Serial.print("\nSpeed of light (m/s):\t");
+  Serial.println(R.getC());
+
+  for (uint8_t p = 0; p < 4; p++)
+  {
+    Serial.print(p);
+    Serial.print(":\t");
+    Serial.println(R.gravitationalTime(1, R.getPlanetMass(p), R.getPlanetRadius(p)));
+  }
+
+  Serial.println("\ndone...");
+}
+
+
+void loop()
+{
+}
+
+// -- END OF FILE --

libraries/relativity/examples/relativity_demo/relativity_demo.ino

@@ -0,0 +1,51 @@
+//
+//    FILE: relativity_demo.ino
+//  AUTHOR: Rob Tillaart
+// VERSION: 0.1.0
+// PURPOSE: test formulas
+//    DATE: 2021-05-29
+//     URL: https://github.com/RobTillaart/relativity
+
+
+#include "relativity.h"
+
+relativity R;
+
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+
+  Serial.print("\nSpeed of light (m/s):\t");
+  Serial.println(R.getC());
+
+  Serial.println("\n Percentage\t Speed\t\t Time\t\t Length\t\t Mass\n");
+
+  for (double perc = 1; perc < 99.9999; perc += (100 - perc) / 10)
+  {
+    double v = R.getC() * perc * 0.01;
+
+    Serial.print(" ");
+    Serial.print(perc, 5);
+    Serial.print("\t ");
+    Serial.print(v * 0.001);
+    Serial.print("\t ");
+    Serial.print(R.relativeTime(1, v), 5);
+    Serial.print("\t ");
+    Serial.print(R.relativeLength(1, v ), 5);
+    Serial.print("\t ");
+    Serial.print(R.relativeMass(1, v), 3);
+    Serial.print("\t ");
+    Serial.print(R.EnergyMass(1, v), 2);
+    Serial.println();
+  }
+  Serial.println("done...");
+}
+
+
+void loop()
+{
+}
+
+// -- END OF FILE --

libraries/relativity/library.json

@@ -0,0 +1,22 @@
+{
+  "name": "relativity",
+  "keywords": "relativity, speed of light, time, length, mass, dilation",
+  "description": "library with relativity functions.",
+  "authors":
+  [
+    {
+      "name": "Rob Tillaart",
+      "email": "[email protected]",
+      "maintainer": true
+    }
+  ],
+  "repository":
+  {
+    "type": "git",
+    "url": "https://github.com/RobTillaart/relativity.git"
+  },
+  "version": "0.1.0",
+  "license": "MIT",
+  "frameworks": "*",
+  "platforms": "*"
+}