refactor as a package

sho/num.py

@@ -0,0 +1,48 @@
+import numpy as np
+
+from . import pb
+
+########################################################################
+# Objective functions
+########################################################################
+
+# Decoupled from objective functions, so as to be used in display.
+def to_sensors(sol):
+    """Convert a vector of n*2 dimension to an array of n 2-tuples.
+
+    >>> to_sensors([0,1,2,3])
+    [(0, 1), (2, 3)]
+    """
+    sensors = []
+    for i in range(0,len(sol),2):
+        sensors.append( ( int(round(sol[i])), int(round(sol[i+1])) ) )
+    return sensors
+
+
+def cover_sum(sol, domain_width, sensor_range):
+    """Compute the coverage quality of the given vector."""
+    domain = np.zeros((domain_width,domain_width))
+    sensors = to_sensors(sol)
+    return np.sum(pb.coverage(domain, sensors, sensor_range))
+
+
+########################################################################
+# Initialization
+########################################################################
+
+def rand(dim, scale):
+    """Draw a random vector in [0,scale]**dim."""
+    return np.random.random(dim) * scale
+
+
+########################################################################
+# Neighborhood
+########################################################################
+
+def neighb_square(sol, scale):
+    """Draw a random vector in a square of witdh `scale`
+    around the given one."""
+    # TODO handle constraints
+    new = sol + (np.random.random(len(sol)) * scale - scale/2)
+    return new
+