Join/inner_joins.ipynb

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        "    <td><a target=\"_blank\"  href=\"https://github.com/giswqs/earthengine-py-notebooks/tree/master/Join/inner_joins.ipynb\"><img width=32px src=\"https://www.tensorflow.org/images/GitHub-Mark-32px.png\" /> View source on GitHub</a></td>\n",
        "    <td><a target=\"_blank\"  href=\"https://nbviewer.jupyter.org/github/giswqs/earthengine-py-notebooks/blob/master/Join/inner_joins.ipynb\"><img width=26px src=\"https://upload.wikimedia.org/wikipedia/commons/thumb/3/38/Jupyter_logo.svg/883px-Jupyter_logo.svg.png\" />Notebook Viewer</a></td>\n",
        "    <td><a target=\"_blank\"  href=\"https://colab.research.google.com/github/giswqs/earthengine-py-notebooks/blob/master/Join/inner_joins.ipynb\"><img src=\"https://www.tensorflow.org/images/colab_logo_32px.png\" /> Run in Google Colab</a></td>\n",
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        "## Install Earth Engine API and geemap\n",
        "Install the [Earth Engine Python API](https://developers.google.com/earth-engine/python_install) and [geemap](https://geemap.org). The **geemap** Python package is built upon the [ipyleaflet](https://github.com/jupyter-widgets/ipyleaflet) and [folium](https://github.com/python-visualization/folium) packages and implements several methods for interacting with Earth Engine data layers, such as `Map.addLayer()`, `Map.setCenter()`, and `Map.centerObject()`.\n",
        "The following script checks if the geemap package has been installed. If not, it will install geemap, which automatically installs its [dependencies](https://github.com/giswqs/geemap#dependencies), including earthengine-api, folium, and ipyleaflet."
      ]
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    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "# Installs geemap package\n",
        "import subprocess\n",
        "\n",
        "try:\n",
        "    import geemap\n",
        "except ImportError:\n",
        "    print('Installing geemap ...')\n",
        "    subprocess.check_call([\"python\", '-m', 'pip', 'install', 'geemap'])"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "import ee\n",
        "import geemap"
      ],
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      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Create an interactive map \n",
        "The default basemap is `Google Maps`. [Additional basemaps](https://github.com/giswqs/geemap/blob/master/geemap/basemaps.py) can be added using the `Map.add_basemap()` function. "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "Map = geemap.Map(center=[40,-100], zoom=4)\n",
        "Map"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Add Earth Engine Python script "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "# Add Earth Engine dataset\n",
        "# Make a date filter to get images in this date range.\n",
        "dateFilter = ee.Filter.date('2014-01-01', '2014-02-01')\n",
        "\n",
        "# Load a MODIS collection with EVI data.\n",
        "mcd43a4 = ee.ImageCollection('MODIS/MCD43A4_006_EVI') \\\n",
        "    .filter(dateFilter)\n",
        "\n",
        "# Load a MODIS collection with quality data.\n",
        "mcd43a2 = ee.ImageCollection('MODIS/006/MCD43A2') \\\n",
        "    .filter(dateFilter)\n",
        "\n",
        "# Define an inner join.\n",
        "innerJoin = ee.Join.inner()\n",
        "\n",
        "# Specify an equals filter for image timestamps.\n",
        "filterTimeEq = ee.Filter.equals(**{\n",
        "  'leftField': 'system:time_start',\n",
        "  'rightField': 'system:time_start'\n",
        "})\n",
        "\n",
        "# Apply the join.\n",
        "innerJoinedMODIS = innerJoin.apply(mcd43a4, mcd43a2, filterTimeEq)\n",
        "\n",
        "# Display the join result: a FeatureCollection.\n",
        "print('Inner join output:', innerJoinedMODIS)\n",
        "\n",
        "# Map a function to merge the results in the output FeatureCollection.\n",
        "joinedMODIS = innerJoinedMODIS.map(lambda feature: ee.Image.cat(feature.get('primary'), feature.get('secondary')))\n",
        "\n",
        "# Print the result of merging.\n",
        "print('Inner join, merged bands:', joinedMODIS.getInfo())\n",
        "\n"
      ],
      "outputs": [],
      "execution_count": null
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "## Display Earth Engine data layers "
      ]
    },
    {
      "cell_type": "code",
      "metadata": {},
      "source": [
        "Map.addLayerControl() # This line is not needed for ipyleaflet-based Map.\n",
        "Map"
      ],
      "outputs": [],
      "execution_count": null
    }
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