tmp commit - toward 0.0.1

pina/cube.py

@@ -0,0 +1,29 @@
+import numpy as np
+from .chebyshev import chebyshev_roots
+
+class Cube():
+    def __init__(self, bound):
+        self.bound = np.asarray(bound)
+
+    def discretize(self, n, mode='random'):
+
+        if mode == 'random':
+            pts = np.random.uniform(size=(n, self.bound.shape[0]))
+        elif mode == 'chebyshev':
+            pts = np.array([chebyshev_roots(n) *.5 + .5 for _ in range(self.bound.shape[0])])
+            grids = np.meshgrid(*pts)
+            pts = np.hstack([grid.reshape(-1, 1) for grid in grids])
+        elif mode == 'grid':
+            pts = np.array([np.linspace(0, 1, n)  for _ in range(self.bound.shape[0])])
+            grids = np.meshgrid(*pts)
+            pts = np.hstack([grid.reshape(-1, 1) for grid in grids])
+        elif mode == 'lh' or mode == 'latin':
+            from scipy.stats import qmc
+            sampler = qmc.LatinHypercube(d=self.bound.shape[0])
+            pts = sampler.random(n)
+
+        # Scale pts
+        pts *= self.bound[:, 1] - self.bound[:, 0]
+        pts += self.bound[:, 0]
+
+        return pts