Pythagorean calculation with sub-optimal numerics (#10575)

Author: DimitriPapadopoulos

xarray/tests/test_plot.py

@@ -595,7 +595,7 @@ def test_geo_data(self) -> None:
                 [-137.85, -120.99, -103.28, -85.28, -67.62],
             ]
         )
-        data = np.sqrt(lon**2 + lat**2)
+        data = np.hypot(lon, lat)
         da = DataArray(
             data,
             dims=("y", "x"),
@@ -3183,8 +3183,8 @@ def test_plot_transposes_properly(plotfunc) -> None:
 def test_facetgrid_single_contour() -> None:
     # regression test for GH3569
     x, y = np.meshgrid(np.arange(12), np.arange(12))
-    z = xr.DataArray(np.sqrt(x**2 + y**2))
-    z2 = xr.DataArray(np.sqrt(x**2 + y**2) + 1)
+    z = xr.DataArray(np.hypot(x, y))
+    z2 = xr.DataArray(np.hypot(x, y) + 1)
     ds = xr.concat([z, z2], dim="time")
     ds["time"] = [0, 1]