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pythonmatplotlibgeopandaskml

Why are the results different by Google Maps and Matplotlib?

I plotted a kml file using matplotlib and showed it on Google Maps, but the line is different. Can anyone tell me why? How can I plot it just like in Google Maps?

<?xml version="1.0" encoding="UTF-8"?>
<kml xmlns="http://www.opengis.net/kml/2.2">
  <Document>
    <name>2019年06月05日黄海海阳泰瑞号长征十一号海</name>
    <Style id="line-000000-1200-normal">
      <LineStyle>
        <color>ff000000</color>
        <width>1.2</width>
      </LineStyle>
    </Style>
    <Style id="line-000000-1200-highlight">
      <LineStyle>
        <color>ff000000</color>
        <width>1.8</width>
      </LineStyle>
    </Style>
    <StyleMap id="line-000000-1200">
      <Pair>
        <key>normal</key>
        <styleUrl>#line-000000-1200-normal</styleUrl>
      </Pair>
      <Pair>
        <key>highlight</key>
        <styleUrl>#line-000000-1200-highlight</styleUrl>
      </Pair>
    </StyleMap>
    <Style id="poly-3949AB-1000-255-normal">
      <LineStyle>
        <color>ffab4939</color>
        <width>1</width>
      </LineStyle>
      <PolyStyle>
        <color>ffab4939</color>
        <fill>1</fill>
        <outline>1</outline>
      </PolyStyle>
    </Style>
    <Style id="poly-3949AB-1000-255-highlight">
      <LineStyle>
        <color>ffab4939</color>
        <width>1.5</width>
      </LineStyle>
      <PolyStyle>
        <color>ffab4939</color>
        <fill>1</fill>
        <outline>1</outline>
      </PolyStyle>
    </Style>
    <StyleMap id="poly-3949AB-1000-255">
      <Pair>
        <key>normal</key>
        <styleUrl>#poly-3949AB-1000-255-normal</styleUrl>
      </Pair>
      <Pair>
        <key>highlight</key>
        <styleUrl>#poly-3949AB-1000-255-highlight</styleUrl>
      </Pair>
    </StyleMap>
    <Placemark>
      <name>ZSHA/A2585/19</name>
      <description><![CDATA[description: <br>名前: ]]></description>
      <styleUrl>#line-000000-1200</styleUrl>
      <ExtendedData>
        <Data name="description">
          <value/>
        </Data>
        <Data name="名前">
          <value/>
        </Data>
      </ExtendedData>
      <LineString>
        <tessellate>1</tessellate>
        <coordinates>
          121.409097,34.899247,0
          121.407996,34.881579,0
          121.404801,34.864084,0
          121.399542,34.846932,0
          121.392271,34.830286,0
          121.38306,34.814308,0
          121.371999,34.79915,0
          121.359193,34.784958,0
          121.344768,34.771868,0
          121.328861,34.760006,0
          121.311627,34.749485,0
          121.29323,34.740406,0
          121.273848,34.732857,0
          121.253665,34.726909,0
          121.232876,34.722619,0
          121.211679,34.720028,0
          121.190278,34.719162,0
          121.168876,34.720028,0
          121.147679,34.722619,0
          121.12689,34.726909,0
          121.106708,34.732857,0
          121.087325,34.740406,0
          121.068929,34.749485,0
          121.051694,34.760006,0
          121.035788,34.771868,0
          121.021362,34.784958,0
          121.008557,34.79915,0
          120.997495,34.814308,0
          120.988284,34.830286,0
          120.981014,34.846932,0
          120.975755,34.864084,0
          120.972559,34.881579,0
          120.971459,34.899247,0
          120.972466,34.91692,0
          120.975572,34.934426,0
          120.980748,34.951596,0
          120.987946,34.968266,0
          120.997098,34.984274,0
          121.008115,34.999465,0
          121.020893,35.013694,0
          121.03531,35.026821,0
          121.051225,35.038721,0
          121.068487,35.049279,0
          121.086928,35.058391,0
          121.10637,35.06597,0
          121.126625,35.071942,0
          121.147496,35.07625,0
          121.168783,35.078851,0
          121.190278,35.079721,0
          121.211773,35.078851,0
          121.233059,35.07625,0
          121.253931,35.071942,0
          121.274186,35.06597,0
          121.293628,35.058391,0
          121.312069,35.049279,0
          121.32933,35.038721,0
          121.345246,35.026821,0
          121.359662,35.013694,0
          121.37244,34.999465,0
          121.383458,34.984274,0
          121.392609,34.968266,0
          121.399807,34.951596,0
          121.404984,34.934426,0
          121.40809,34.91692,0
          121.409097,34.899247,0
        </coordinates>
      </LineString>
    </Placemark>
    <Placemark>
      <name>ZSHA/A2637/19</name>
      <description><![CDATA[description: <br>名前: ]]></description>
      <styleUrl>#poly-3949AB-1000-255</styleUrl>
      <ExtendedData>
        <Data name="description">
          <value/>
        </Data>
        <Data name="名前">
          <value/>
        </Data>
      </ExtendedData>
      <Polygon>
        <outerBoundaryIs>
          <LinearRing>
            <tessellate>1</tessellate>
            <coordinates>
              124,33.680556,0
              123.628889,33.235556,0
              124.598652,32.687742,0
              124.966694,33.118961,0
              124,33.680556,0
            </coordinates>
          </LinearRing>
        </outerBoundaryIs>
      </Polygon>
    </Placemark>
    <Placemark>
      <name>RKRR/A0864/19</name>
      <description><![CDATA[description: <br>名前: ]]></description>
      <styleUrl>#poly-3949AB-1000-255</styleUrl>
      <ExtendedData>
        <Data name="description">
          <value/>
        </Data>
        <Data name="名前">
          <value/>
        </Data>
      </ExtendedData>
      <Polygon>
        <outerBoundaryIs>
          <LinearRing>
            <tessellate>1</tessellate>
            <coordinates>
              124,33.680556,0
              124,33.023056,0
              124.598652,32.687742,0
              124.966694,33.118961,0
              124,33.680556,0
            </coordinates>
          </LinearRing>
        </outerBoundaryIs>
      </Polygon>
    </Placemark>
    <Placemark>
      <name>RJJJ/J2462/19</name>
      <description><![CDATA[description: <br>名前: ]]></description>
      <styleUrl>#poly-3949AB-1000-255</styleUrl>
      <ExtendedData>
        <Data name="description">
          <value/>
        </Data>
        <Data name="名前">
          <value/>
        </Data>
      </ExtendedData>
      <Polygon>
        <outerBoundaryIs>
          <LinearRing>
            <tessellate>1</tessellate>
            <coordinates>
              135.728611,25.744722,0
              135.224722,25.186111,0
              136.487549,24.20233,0
              137.016389,24.755556,0
              135.728611,25.744722,0
            </coordinates>
          </LinearRing>
        </outerBoundaryIs>
      </Polygon>
    </Placemark>
    <Placemark>
      <name>海上45°轨道</name>
      <description><![CDATA[description: <br>名前: Route]]></description>
      <styleUrl>#line-000000-1200</styleUrl>
      <ExtendedData>
        <Data name="description">
          <value/>
        </Data>
        <Data name="名前">
          <value>Route</value>
        </Data>
      </ExtendedData>
      <LineString>
        <tessellate>1</tessellate>
        <coordinates>
          121.1829579,34.9082773,0
          138.2007802,23.3168334,0
        </coordinates>
      </LineString>
    </Placemark>
  </Document>
</kml>

KML file on Google Map KML file plotted by Matplotlib

Solution

  • You need to plot your KML using an Orthographic map projection to match the Google's view :

    One way would be to use geoplot :

    import geoplot

ax = geoplot.polyplot(
    gpd.read_file("file.kml"), # or gdf's name
    projection=geoplot.crs.Orthographic(),
    figsize=(17, 5),
    facecolor="cyan",
    zorder=2
)

ax.coastlines()
ax.stock_img()

    enter image description here

    In case you're building on top of subplots, you can do :

    gdf = gpd.read_file("file.kml")

xmean, ymean = gdf.centroid.get_coordinates().mean()

proj = geoplot.crs.Orthographic(central_longitude=xmean, central_latitude=ymean)

fig, ax = plt.subplots(figsize=(12, 4), subplot_kw={"projection": proj})

geoplot.polyplot(
    gdf,
    projection=proj,
    facecolor="cyan",
    zorder=2,
    ax=ax,
)

ax.coastlines()
ax.stock_img()