{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "You will need to install the following packages:\n",
    "- `ipyleaflet`\n",
    "- `requests`\n",
    "- `xarray`\n",
    "- `netcdf4`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "from ipyleaflet import Map, Velocity, TileLayer\n",
    "import requests\n",
    "import xarray as xr\n",
    "import os"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "center = [0, 0]\n",
    "zoom = 1\n",
    "m = Map(center=center, zoom=zoom, interpolation='nearest')\n",
    "m"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "tl = TileLayer(url='https://cartodb-basemaps-{s}.global.ssl.fastly.net/dark_all/{z}/{x}/{y}.png')\n",
    "m.add_layer(tl)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "if not os.path.exists('wind-global.nc'):\n",
    "    url = 'https://github.com/benbovy/xvelmap/raw/master/notebooks/wind-global.nc'\n",
    "    r = requests.get(url)\n",
    "    wind_data = r.content\n",
    "    with open('wind-global.nc', 'wb') as f:\n",
    "        f.write(wind_data)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "ds = xr.open_dataset('wind-global.nc')\n",
    "display_options = {\n",
    "    'velocityType': 'Global Wind',\n",
    "    'displayPosition': 'bottomleft',\n",
    "    'displayEmptyString': 'No wind data'\n",
    "}\n",
    "wind = Velocity(data=ds, u_var='u_wind', v_var='v_wind', lat_dim='lat', lon_dim='lon', velocity_scale=0.01, max_velocity=20, display_options=display_options)\n",
    "m.add_layer(wind)"
   ]
  }
 ],
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