added an example of how to save the heat data to a numpy array

numpy_example.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python
+#
+# Plots some random data to a heatmap.  This is not mainly useful for
+# testing and to illustrate how to use heatmap.py from other python code.
+#
+# Copyright 2014 Seth Golub http://www.sethoscope.net/heatmap/
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General
+# Public License along with this program.  If not, see
+# <http://www.gnu.org/licenses/>.
+
+from __future__ import print_function
+
+import random
+import logging
+import sys
+import heatmap as hm
+from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter
+import numpy as np
+
+
+def shapes_generator(count):
+    for i in range(count):
+        a = random.gauss(10, 1.0)
+        b = random.gauss(10, 2.0)
+        yield hm.Point(hm.LatLon(a, b),)
+
+
+def setup_config(count):
+    config = hm.Configuration()
+    config.shapes = shapes_generator(count)
+    config.projection = hm.EquirectangularProjection()
+    config.projection.pixels_per_degree = 30
+    config.decay = 1
+    config.kernel = hm.LinearKernel(5)
+    config.background = 'black'
+    config.fill_missing()
+    return config
+
+
+def matrix_to_numpy(config, matrix):
+    extent = config.extent_out or matrix.extent()
+    arr = np.zeros((int(extent.size().x) + 1,
+                    int(extent.size().y) + 1))
+    for (coord, value) in matrix.items():
+        x = int(coord.x - extent.min.x)
+        y = int(coord.y - extent.min.y)
+        if extent.is_inside(coord):
+            arr[x, y] = value
+            logging.debug('set (%d,%d) to %f' % (x, y, arr[x, y]))
+    return arr
+
+def main():
+    logging.basicConfig(format='%(relativeCreated)8d ms  // %(message)s')
+    description = 'generate random points, save them in a numpy array'
+    parser = ArgumentParser(description=description,
+                            formatter_class=ArgumentDefaultsHelpFormatter)
+    parser.add_argument('--output', metavar='FILE', default='/tmp/out.png')
+    parser.add_argument('-v', '--verbose', action='store_true')
+    parser.add_argument('--debug', action='store_true')
+    parser.add_argument('count', type=int)
+    args = parser.parse_args()
+    if args.verbose:
+        logging.getLogger().setLevel(logging.INFO)
+    if args.debug:
+        logging.getLogger().setLevel(logging.DEBUG)
+
+    logging.debug('python version %s' % str(sys.version))
+
+    config = setup_config(args.count)
+    matrix = hm.process_shapes(config)
+    matrix = matrix.finalized()
+    arr = matrix_to_numpy(config, matrix)
+    print('shape: ' + str(arr.shape))
+    print('max value: %f' % arr.max())
+    nonzero = np.count_nonzero(arr)
+    print('nonzero cells: %d / %d (%d%%)' % (nonzero, arr.size,
+                                             int(100.0 * nonzero / arr.size)))
+
+
+if __name__ == '__main__':
+    main()

test/test_numpy.py

@@ -0,0 +1,25 @@
+#!/usr/bin/env python
+"""Test numpy_example.py.  There's nothing worse than broken examples."""
+
+import os
+import subprocess
+import sys
+
+try:
+    import unittest2 as unittest  # Python 2.6
+except ImportError:
+    import unittest
+
+ROOT_DIR = os.path.split(os.path.abspath(os.path.dirname(__file__)))[0]
+sys.path.append(ROOT_DIR)
+
+
+class Tests(unittest.TestCase):
+    def test_system(self):
+        # We just check that it runs, not that it's correct.
+        subprocess.check_call(
+            [os.path.join(ROOT_DIR, 'numpy_example.py'),
+             '100'])
+
+if __name__ == '__main__':
+    unittest.main()