{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Example usage\n",
    "\n",
    "Here we will demonstrate how to use `pyvlasiator` to process Vlasiator data."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Downloading demo data\n",
    "\n",
    "If you don't have Vlasiator data to start with, you can download demo data with the following:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "import requests\n",
    "import tarfile\n",
    "import os\n",
    "\n",
    "url = \"https://raw.githubusercontent.com/henry2004y/vlsv_data/master/testdata.tar.gz\"\n",
    "testfiles = url.rsplit(\"/\", 1)[1]\n",
    "r = requests.get(url, allow_redirects=True)\n",
    "open(testfiles, \"wb\").write(r.content)\n",
    "path = \"./data\"\n",
    "if not os.path.exists(path):\n",
    "   os.makedirs(path)\n",
    "with tarfile.open(testfiles) as file:\n",
    "   file.extractall(path)\n",
    "os.remove(testfiles)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Loading VLSV data\n",
    "\n",
    "### Read meta data"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "from pyvlasiator.vlsv import Vlsv\n",
    "\n",
    "file = \"data/bulk.1d.vlsv\"\n",
    "meta = Vlsv(file)\n",
    "meta"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Read parameters"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "t = meta.read_parameter(\"time\")\n",
    "t"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Read variable"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "data = meta.read_variable(\"CellID\")\n",
    "data"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Plotting\n",
    "\n",
    "To enable plotting functionalities, we need to first import the corresponding submodule:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "import pyvlasiator.plot"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### 1D"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "meta.plot(\"proton/vg_rho\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### 2D"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "file = \"data/bulk.2d.vlsv\"\n",
    "meta = Vlsv(file)\n",
    "meta.pcolormesh(\"vg_b_vol\", comp=1)\n",
    "meta.streamplot(\"proton/vg_v\", comp=\"xy\", color=\"w\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Field solver grid variables are also supported via the same APIs:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "meta.pcolormesh(\"fg_b\", comp=1)\n",
    "meta.streamplot(\"fg_b\", comp=\"xy\", color=\"w\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## 2D slice of 3D AMR data"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "file = \"data/bulk.amr.vlsv\"\n",
    "meta = Vlsv(file)\n",
    "meta.pcolormesh(\"proton/vg_rho\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## VDF"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "vscode": {
     "languageId": "julia"
    }
   },
   "outputs": [],
   "source": [
    "file = \"data/bulk.1d.vlsv\"\n",
    "meta = Vlsv(file)\n",
    "loc = [2.0, 0.0, 0.0]\n",
    "meta.vdfslice(loc)"
   ]
  }
 ],
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