change interpolant for irregular grid in topotools_examples.ipynb

notebooks/geoclaw/topotools_examples.ipynb

@@ -238,6 +238,7 @@
  "metadata": {},
  "source": [
  "<div id=crop></div>\n",
+ "\n",
  "## Cropping topography\n",
  "\n",
  "Sometimes it is useful to crop a large topo file to create a smaller one that contains a sub-region, e.g."
@@ -302,6 +303,7 @@
  "metadata": {},
  "source": [
  "<div id=coarsen></div>\n",
+ "\n",
  "## Coarsening topography\n",
  "\n",
  "The `crop` function also has an optional argument `coarsen` with default value 1. If the value is larger integer than it coarsens the grid by that factor in each direction.\n",
@@ -332,6 +334,7 @@
  "metadata": {},
  "source": [
  "<div id=unstructured></div>\n",
+ "\n",
  "## Unstructured Topography"
  ]
  },
@@ -350,18 +353,30 @@
  "source": [
  "import scipy.interpolate as interpolate\n",
  "\n",
+ "# Here we need to transpose the Z array so that the coordinate evaluation is correct\n",
+ "bathy = interpolate.RegularGridInterpolator((topo.x, topo.y), topo.Z.transpose())"
+ ]
+ },
+ {
+ "cell_type": "markdown",
+ "metadata": {},
+ "source": [
+ "Now choose `N` random points and evaluate the interpolant at these points:"
+ ]
+ },
+ {
+ "cell_type": "code",
+ "execution_count": null,
+ "metadata": {},
+ "outputs": [],
+ "source": [
  "N = 10000\n",
  "\n",
  "x = numpy.random.rand(N) * (topo.x[-1] - topo.x[0]) + topo.x[0]\n",
  "y = numpy.random.rand(N) * (topo.y[-1] - topo.y[0]) + topo.y[0]\n",
  "\n",
- "# Here we need to transpose the Z array so that the coordinate evaluation is correct\n",
- "bathy = interpolate.RectBivariateSpline(topo.x, topo.y, topo.Z.transpose())\n",
- "\n",
- "# strange hack to evaluate the function `bathy` produced by RectBivariateSpline since bathy(x, y) does not work\n",
- "z = numpy.empty(x.shape)\n",
- "for i in range(x.shape[0]):\n",
- " z[i] = bathy(x[i], y[i])"
+ "xypts = array(list(zip(x,y)))\n",
+ "z = bathy(xypts)"
  ]
  },
  {
@@ -475,9 +490,9 @@
  ],
  "metadata": {
  "kernelspec": {
- "display_name": "Python 2",
+ "display_name": "Python 3 (ipykernel)",
  "language": "python",
- "name": "python2"
+ "name": "python3"
  },
  "language_info": {
  "codemirror_mode": {
@@ -489,9 +504,9 @@
  "name": "python",
  "nbconvert_exporter": "python",
  "pygments_lexer": "ipython3",
- "version": "3.6.2"
+ "version": "3.10.13"
  }
  },
  "nbformat": 4,
- "nbformat_minor": 1
+ "nbformat_minor": 4
 }