Added a logarithmic spiral for sampling points.

1 files changed, 197 insertions, 0 deletions

diff --git a/ep_sampler_logarithmicspiral.py b/ep_sampler_logarithmicspiral.py
new file mode 100644
index 0000000..c855812
--- /dev/null
+++ b/ep_sampler_logarithmicspiral.py
@@ -0,0 +1,197 @@
+# coding: UTF-8
+# Copyright 2009, 2010 Thomas Jourdan
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+import ka_utils
+import model_random
+import model_locus
+import model_allele
+import model_constraintpool
+from gettext import gettext as _
+import math
+
+X_CENTER_CONSTRAINT = 'xcenterconstraint'
+Y_CENTER_CONSTRAINT = 'ycenterconstraint'
+TURNS_CONSTRAINT = 'turnsconstraint'
+STEPS_CONSTRAINT = 'stepsconstraint'
+A_CONSTRAINT = 'aconstraint'
+B_CONSTRAINT = 'bconstraint'
+
+class LogarithmicSpiralSampler(model_allele.Allele):
+    """LogarithmicSpiralSampler: Reverse the layer horizontally or vertically.
+    inv: self.a >= 0.0
+    inv: self.b >= 0.0
+    inv: self.steps >= 1
+    """
+
+    cdef = [{'bind'  : X_CENTER_CONSTRAINT,
+             'name'  : 'Center point x',
+             'domain': model_constraintpool.FLOAT_RANGE,
+             'min'   : -1.0, 'max': 2.0},
+             {'bind'  : Y_CENTER_CONSTRAINT,
+             'name'  : 'Center point y',
+             'domain': model_constraintpool.FLOAT_RANGE,
+             'min'   : -1.0, 'max': 2.0},
+             {'bind'  : TURNS_CONSTRAINT,
+             'name'  : 'Revolution of logarithmic spiral',
+             'domain': model_constraintpool.FLOAT_RANGE,
+             'min'   : -10.0, 'max': 10.0},
+             {'bind'  : STEPS_CONSTRAINT,
+             'name'  : 'Number of samples per revolution.',
+             'domain': model_constraintpool.INT_RANGE,
+             'min'   : 3, 'max': 36},
+             {'bind'  : A_CONSTRAINT,
+             'name'  : 'Scaling constant for logarithmic spiral',
+             'domain': model_constraintpool.FLOAT_RANGE,
+             'min'   : 0.0, 'max': 1.0},
+             {'bind'  : B_CONSTRAINT,
+             'name'  : 'Scaling constant for logarithmic spiral',
+             'domain': model_constraintpool.FLOAT_RANGE,
+             'min'   : 0.0, 'max': 1.0},
+           ]                                                  
+
+    def __init__(self, trunk):
+        """Constructor for a flip merger."""
+        super(LogarithmicSpiralSampler, self).__init__(trunk)
+        self.x_center = 0.5
+        self.y_center = 0.5
+        self.steps = 1
+        self.turns = 1.0
+        self.a = 1.0
+        self.b = 1.0
+
+    def __eq__(self, other):
+        """Equality based on fliping horizontally or vertically."""
+        equal = isinstance(other, LogarithmicSpiralSampler) \
+                and self.x_center == other.x_center \
+                and self.y_center == other.y_center \
+                and self.steps == other.steps \
+                and self.turns == other.turns \
+                and self.a == other.a \
+                and self.b == other.b
+        return equal
+
+    def randomize(self):
+        """Randomize"""
+        cpool = model_constraintpool.ConstraintPool.get_pool()
+        x_center_constraint = cpool.get(self, X_CENTER_CONSTRAINT)
+        self.x_center = model_random.uniform_constrained(x_center_constraint)
+        y_center_constraint = cpool.get(self, Y_CENTER_CONSTRAINT)
+        self.y_center = model_random.uniform_constrained(y_center_constraint)
+        y_steps_constraint = cpool.get(self, STEPS_CONSTRAINT)
+        self.steps = model_random.randint_constrained(y_steps_constraint)
+        turns_constraint = cpool.get(self, TURNS_CONSTRAINT)
+        self.turns = model_random.uniform_constrained(turns_constraint)
+        a_constraint = cpool.get(self, A_CONSTRAINT)
+        self.a = model_random.uniform_constrained(a_constraint)
+        b_constraint = cpool.get(self, B_CONSTRAINT)
+        self.b = model_random.uniform_constrained(b_constraint)
+
+    def mutate(self):
+        """Mutate"""
+        cpool = model_constraintpool.ConstraintPool.get_pool()
+        x_center_constraint = cpool.get(self, X_CENTER_CONSTRAINT)
+        self.x_center = model_random.jitter_constrained(self.x_center,
+                                                        x_center_constraint)
+        y_center_constraint = cpool.get(self, Y_CENTER_CONSTRAINT)
+        self.y_center = model_random.jitter_constrained(self.y_center,
+                                                        y_center_constraint)
+        if model_random.is_mutating():
+            steps_constraint = cpool.get(self, STEPS_CONSTRAINT)
+            self.steps = model_random.jitter_discret_constrained(self.steps,
+                                                            steps_constraint)
+        turns_constraint = cpool.get(self, TURNS_CONSTRAINT)
+        self.turns = model_random.jitter_constrained(self.turns,
+                                                        turns_constraint)
+        a_constraint = cpool.get(self, A_CONSTRAINT)
+        self.a = model_random.jitter_constrained(self.a, a_constraint)
+        b_constraint = cpool.get(self, B_CONSTRAINT)
+        self.b = model_random.jitter_constrained(self.b, b_constraint)
+
+    def swap_places(self):
+        """Exchange x- and y-center."""
+        self.x_center, self.y_center = model_random.swap_parameters(self.x_center,
+                                                                    self.y_center)
+
+    def crossingover(self, other):
+        """
+        pre: isinstance(other, LogarithmicSpiralSampler)
+        pre: isinstance(self, LogarithmicSpiralSampler)
+        # check for distinct references, needs to copy content, not references
+        post: __return__ is not self
+        post: __return__ is not other
+        post: model_locus.unique_check(__return__, self, other) == ''
+        """
+        new_one = LogarithmicSpiralSampler(self.get_trunk())
+        cross_sequence = model_random.crossing_sequence(2)
+        new_one.x_center = self.x_center if cross_sequence[0] else other.x_center
+        new_one.y_center = self.y_center if cross_sequence[1] else other.y_center
+        new_one.steps = self.steps if cross_sequence[2] else other.steps
+        new_one.turns = self.turns if cross_sequence[3] else other.turns
+        new_one.a = self.a if cross_sequence[4] else other.a
+        new_one.b = self.b if cross_sequence[5] else other.b
+        return new_one
+
+    def get_sample_points(self):
+        """ Produces a list of sampling points.
+        """
+        sample_points = []
+        ox, oy = self.x_center, self.y_center
+        angularStep = (2 * math.pi) / self.steps
+        turns = self.turns
+        ccw = 1
+        if turns < 0:
+            turns = -turns
+            ccw = -1
+        for n in range(int(turns * self.steps)):
+            phi = n * angularStep
+            a2, b2  = self.a**2, self.b**2
+            r = a2 * math.exp(b2 * phi)
+            x = ox + r * math.cos(ccw * phi)
+            y = oy + r * math.sin(ccw * phi)
+            if math.fabs(x) < 1000 and math.fabs(y) < 1000:
+                sample_points.append( (x, y) )
+        return sample_points
+
+    def get_sample_extent(self):
+        """'Size' of one sample as a fraction of 1.
+        """
+        size = 1.0/self.steps
+        return size, size
+
+    def explain(self):
+        """
+        post: len(__return__) == 3
+        """
+        head = _('Logarithmic spiral sampler: center=%f,%f, revolutions=%f, steps per revolution=%d, a=%f, b=%f') \
+                                    % (self.x_center, self.y_center,
+                                       self.turns, self.steps, self.a, self.b)
+        return ka_utils.explain_points(head, self.get_sample_points())
+
+    def copy(self):
+        """A copy constructor.
+        post: isinstance(__return__, LogarithmicSpiralSampler)
+        # check for distinct references, needs to copy content, not references
+        post: __return__ is not self
+        """
+        new_one = LogarithmicSpiralSampler(self.get_trunk())
+        new_one.x_center = self.x_center
+        new_one.y_center = self.y_center
+        new_one.steps = self.steps
+        new_one.turns = self.turns
+        new_one.a = self.a
+        new_one.b = self.b
+        return new_one