Number distributions API.

utils/adaptive_curve.py

@@ -11,6 +11,7 @@
 import random
 
 from sverchok.utils.logging import debug, info, exception
+from sverchok.utils.math import distribute_int
 from sverchok.utils.curve import SvCurve, SvCurveLengthSolver
 
 class CurvePopulationController(object):
@@ -72,6 +73,25 @@ def get_points_count(self, idx):
             ppe += 2
         return ppe
 
+def populate_t_segment(key_ts, target_count):
+    """
+    Given key values of T parameter and target number of values,
+    return list of T values distributed so that each span
+    between key T values includes number of values proportional
+    to span's size.
+    For example,
+    populate_t_segment([0, 1, 3], 7) = [0, 0.5, 1, 1.5, 2, 2.5, 3]
+    """
+    key_ts = np.asarray(key_ts)
+    count_new = target_count - len(key_ts)
+    sizes = key_ts[1:] - key_ts[:-1]
+    counts = distribute_int(count_new, sizes)
+    result = set(key_ts)
+    for count, t_max, t_min in zip(counts, key_ts[1:], key_ts[:-1]):
+        ts = np.linspace(t_min, t_max, num=count+2)[1:-1]
+        result.update(ts)
+    return np.asarray(list(sorted(result)))
+
 def populate_curve(curve, samples_t, by_length = False, by_curvature = True, population_controller = None, curvature_clip = 100, seed = None):
     if population_controller is None:
         population_controller = MinMaxPerSegment(1, 5)

utils/math.py

@@ -385,6 +385,17 @@ def _gcd(a, b):
     return a
 
 def distribute_int(n, sizes):
+    """
+    Distribute the integer number (`n`) of items among several buckets of
+    different sizes, so that the number of items in each bucket is proportional
+    to bucket's size.
+    Parameters:
+    * n - total number of items (integer)
+    * sizes - sizes of buckets do distribute between (list of numbers)
+    Output:
+    * list of integers: for each bucket, the number of items to be put
+        into that bucket. Sum of all numbers in this list is always equal to `n`.
+    """
     total_size = sum(sizes)
     ratios = [size / total_size for size in sizes]
     counts = [int(n * ratio) for ratio in ratios]