more detailed streamlines

flowmap/particles.py

@@ -9,7 +9,7 @@
 def make_tracer_pipeline(
         polydata,
         seed,
-        maximum_number_of_steps=200,
+        maximum_number_of_steps=3000,
         maximum_propagation=1000
 ):
     """Make a tracer pileine based on a polydata and seed.

notebooks/create_quiver.ipynb

@@ -0,0 +1,109 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import netCDF4\n",
+    "import geojson\n",
+    "import numpy as np\n",
+    "import shapely.geometry"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "ds = netCDF4.Dataset('/Users/baart_f/data/rijnland/vanGovert/Leerdam/leerdamwest_map.nc')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 22,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "\n",
+    "x = ds.variables['mesh2d_face_x'][:]\n",
+    "y = ds.variables['mesh2d_face_y'][:]\n",
+    "ucx = ds.variables['mesh2d_ucx'][-1]\n",
+    "ucy = ds.variables['mesh2d_ucy'][-1]\n",
+    "angles = np.rad2deg(np.arctan2(ucy, ucx))\n",
+    "lengths = np.sqrt(ucx ** 2 + ucy **2 )"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 34,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "crs = geojson.crs.Named(\n",
+    "    properties={\n",
+    "        \"name\": \"urn:ogc:def:crs:EPSG::{:d}\".format(28992)\n",
+    "    }\n",
+    ")\n",
+    "features= []\n",
+    "for i, (x_i, y_i, angle_i, length_i, u_i, v_i) in enumerate(zip(x, y, angles, lengths, ucx, ucy)):\n",
+    "    point = shapely.geometry.Point(x_i, y_i)\n",
+    "    geometry = point.__geo_interface__\n",
+    "    geometry['crs'] = dict(crs)\n",
+    "    feature = geojson.Feature(\n",
+    "        id=i, \n",
+    "        geometry=geometry, \n",
+    "        properties={\n",
+    "            \"angle_east_ccw\": angle_i,\n",
+    "            \"angle_north_cw\": 90 - angle_i,\n",
+    "            \"length\": length_i,\n",
+    "            \"u\": u_i,\n",
+    "            \"v\": v_i\n",
+    "        }\n",
+    "    )\n",
+    "    features.append(feature)\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 35,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "fc = geojson.FeatureCollection(features=features)\n",
+    "with open('quiver.json', 'w') as f:\n",
+    "    geojson.dump(fc, f)\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.6.5"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}