{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {
    "id": "colab-badge"
   },
   "source": [
    "[![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/seap-udea/MultiNEAs/blob/main/examples/population_asteroid_tutorial.ipynb)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# MultiNEAs: The `population.Asteroid` Class Tutorial\n",
    "\n",
    "This notebook demonstrates how to use the `multineas.population.Asteroid` class for converting between asteroid diameter and absolute magnitude."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Installation\n",
    "\n",
    "If you're running this in Google Colab or need to install the package, uncomment and run the following cell:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "try:\n",
    "    from google.colab import drive\n",
    "    %pip install -Uq multineas\n",
    "except ImportError:\n",
    "    print(\"Not running in Colab, skipping installation\")\n",
    "\n",
    "# Uncomment to install from GitHub (development version)\n",
    "# !pip install git+https://github.com/seap-udea/MultiNEAs.git"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Load the Package\n",
    "\n",
    "Import `multineas.population` and `matplotlib.pyplot`:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "%load_ext autoreload\n",
    "%autoreload 2\n",
    "import numpy as np\n",
    "import matplotlib.pyplot as plt\n",
    "from multineas.population import Asteroid\n",
    "import warnings\n",
    "%matplotlib inline\n",
    "\n",
    "warnings.filterwarnings(\"ignore\")\n",
    "from multineas.plot import multineas_watermark"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Convert Absolute Magnitude to Diameter\n",
    "\n",
    "We can use `Asteroid.hmag_to_diameter` to convert absolute magnitude ($H$) to diameter ($D$). The default albedo is 0.15."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "H = 18.0\n",
    "diameter = Asteroid.hmag_to_diameter(H)\n",
    "print(f\"For H = {H}, Diameter = {diameter:.3f} km\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You can also specify a different albedo:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "albedo = 0.05\n",
    "diameter_low_albedo = Asteroid.hmag_to_diameter(H, albedo=albedo)\n",
    "print(f\"For H = {H} and albedo = {albedo}, Diameter = {diameter_low_albedo:.3f} km\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Convert Diameter to Absolute Magnitude\n",
    "\n",
    "Conversely, use `Asteroid.diameter_to_hmag` to convert diameter to absolute magnitude."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "D = 1.0 # km\n",
    "H_calc = Asteroid.diameter_to_hmag(D)\n",
    "print(f\"For Diameter = {D} km, H = {H_calc:.3f}\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Visualization\n",
    "\n",
    "Let's plot the relationship between H and Diameter for different albedos."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "H_values = np.linspace(10, 30, 100)\n",
    "albedos = [0.05, 0.15, 0.25]\n",
    "\n",
    "fig, ax = plt.subplots(figsize=(8, 6))\n",
    "\n",
    "for p_v in albedos:\n",
    "    D_values = Asteroid.hmag_to_diameter(H_values, albedo=p_v)\n",
    "    ax.plot(H_values, D_values, label=f\"Albedo = {p_v}\")\n",
    "\n",
    "ax.set_xlabel(\"Absolute Magnitude (H)\")\n",
    "ax.set_ylabel(\"Diameter (km)\")\n",
    "ax.set_yscale(\"log\")\n",
    "ax.set_title(\"Diameter vs. Absolute Magnitude\")\n",
    "ax.legend()\n",
    "ax.grid(True, which=\"both\", ls=\"-\", alpha=0.5)\n",
    "\n",
    "multineas_watermark(ax)\n",
    "\n",
    "plt.show()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Attribution\n",
    "\n",
    "The `Asteroid` class is part of the `multineas` package."
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "Python 3",
   "language": "python",
   "name": "python3"
  },
  "language_info": {
   "codemirror_mode": {
    "name": "ipython",
    "version": 3
   },
   "file_extension": ".py",
   "mimetype": "text/x-python",
   "name": "python",
   "nbconvert_exporter": "python",
   "pygments_lexer": "ipython3",
   "version": "3.8.5"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 4
}