add script to generate oscillator configs

miniapps/oscillators/README.md

@@ -6,6 +6,10 @@ voxel-wise autocorrelations for all window sizes up to the specified input (via
 `-w` option). It also finds the voxels with the `k` strongest autocorrelations
 (for every shift).
 
+The oscillators' locations and parameters are specified in an input file. See
+inputs folder for examples. The `generate_input.py` script can generate a set
+of randomly initialized oscillators.
+
 The simulation code is in `oscillator.cpp`.
 The analysis interface is specified in `analysis.h`.
 The actual analysis code is in `analysis.cpp`.

miniapps/oscillators/inputs/generate_input.py

+import sys
+import random
+from math import sqrt
+pi = 3.1415
+
+# script to generate new oscillator configs
+# using random values within a set of ranges
+
+# nosc -- number of osciallators to genrate
+# nx,ny -- grid dimensions
+# r0,r1 -- min/max width of the Guassian splat
+# w0,w1 -- min/max frequency
+# z0,z1 -- min/max damping coeficient
+# dfrac -- ratio of damped to periodic type
+
+nosc = 128
+nx = ny = 2048
+
+r0 = 8
+r1 = 96
+
+w0 = pi/4.
+w1 = 16.*pi
+
+z0 = 0.0
+z1 = 1.0
+
+dfrac = 0.75
+
+x0 = r1
+x1 = nx - r1
+
+def rng(x0, x1):
+    return x0 + (x1 - x0)*random.random()
+
+sys.stderr.write('#type    center    r    omega0    zeta\n')
+
+
+max_dist = 0.
+min_dist = x1-x0
+
+pts = []
+
+i = 0
+while i < nosc:
+    x = rng(x0, x1)
+    y = rng(x0, x1)
+    w = rng(w0, w1)
+    r = rng(r0, r1)
+    z = rng(z0, z1)
+    t = 'damped' if random.random() < dfrac else 'periodic'
+    sys.stderr.write('%s    %d %d %d    %f    %f    %f\n'%(t,x,y,0.,r,w,z))
+    pts += [x,y,z]
+    i += 1
+
+i = 0
+while i < nosc:
+    xa = pts[3*i]
+    ya = pts[3*i + 1]
+    za = pts[3*i + 2]
+    j = 0
+    while j < nosc:
+        if i != j:
+            xb = pts[3*j]
+            yb = pts[3*j + 1]
+            zb = pts[3*j + 2]
+            dx = xb - xa
+            dy = yb - ya
+            dz = zb - za
+            max_dist = max(max_dist, sqrt(dx**2+dy**2+dz**2))
+            min_dist = min(min_dist, sqrt(dx**2+dy**2+dz**2))
+        j += 1
+    i += 1
+
+sys.stderr.write('# max_dist = %f\n'%(max_dist))
+sys.stderr.write('# min_dist = %f\n'%(min_dist))
+