Changes between Version 2 and Version 3 of misc/setup_for_ML/example_beamsize

Timestamp:

09/13/23 16:17:47 (22 months ago)

Author:

Takashi Obina

Comment:

--

misc/setup_for_ML/example_beamsize

@@ -26 +26 @@
 
 {{{
+import GPy
+import GPyOpt
+import matplotlib.pyplot as plt
+import numpy as np
+import time
 
+from ocelot import *
+from ocelot.gui.accelerator import *
+
+def func(x):
+    global cnt, QM1, QM2, tws, lat, tws0
+    x0=x[:,0][0]
+    x1=x[:,1][0]
+
+    # update optics
+    QM1.k1 = x0
+    QM2.k1 = x1
+    lat.update_transfer_maps()
+    tws = twiss(lat, tws0, nPoints=1000)
+
+    idx = -1  # last point of the lattice
+    sx = np.sqrt(tws[idx].beta_x)
+    sy = np.sqrt(tws[idx].beta_y)
+
+    # Evaluation Function Example
+    val = np.abs(sx) + np.abs(sy)
+    # val = np.abs(sx*sy)
+    # val = np.log(np.abs((sx+10)*(sy+10)))
+    # val = -1.0/np.abs((sx+10)*(sy+10))
+
+    print("%d: %+8.3f,%+8.3f,%+8.3f,%+8.3f,%+8.3f"%(cnt, x0, x1, sx, sy, val))
+    cnt = cnt + 1
+    return val
+
+
+# ==== Main =====
+
+# Define Optics
+## Drift
+L20  = Drift(l=0.2, eid='L20')
+L50  = Drift(l=0.5, eid='L50')
+## Quadrupoles
+QM1 = Quadrupole(l=0.2, k1=3.9, eid='QM1')
+QM2 = Quadrupole(l=0.2, k1=-3.25, eid='QM2')
+## Lattice
+cell = (L50, QM1, L20, QM2, L50, L50)
+lat = MagneticLattice(cell, stop=None)
+print("length of the cell: ", lat.totalLen, " m")
+tws0 = Twiss()
+tws0.beta_x = 20.0
+tws0.beta_y = 30.0
+tws0.alpha_x = -10.0
+tws0.alpha_y = -5.0
+tws0.emit_x = 1.0
+tws0.emit_y = 1.0
+tws0.E = 1.0
+
+tws = twiss(lat, tws0, nPoints=1000)
+
+# GP Optimization
+print("==== start ====")
+print("# cnt, x0, x1, sx, sy, eval_val")
+
+cnt = 0
+bounds = [{'name':'x0', 'type':'continuous', 'domain':(-20, 20)},
+          {'name':'x1', 'type':'continuous', 'domain':(-20, 20)}]
+
+myBopt = GPyOpt.methods.BayesianOptimization(f=func,domain=bounds,initial_design_numdata=10,acquisition_type='LCB')
+
+myBopt.run_optimization(max_iter=50)
+myBopt.plot_acquisition()
+myBopt.plot_convergence()
+print("Best     = ", myBopt.x_opt)
+print("eval_val = ", func(np.array([myBopt.x_opt])))
+
+QM1.k1 = myBopt.x_opt[0]
+QM2.k1 = myBopt.x_opt[1]
+lat.update_transfer_maps()
+tws = twiss(lat, tws0, nPoints=1000)
+
+s = [p.s for p in tws]
+beta_x = [p.beta_x for p in tws]
+beta_y = [p.beta_y for p in tws]
+
+plt.plot(s, beta_x, 'b-');
+plt.plot(s, beta_y, 'r-');
+
+plt.legend(['Horiz', 'Vert'])
+plt.xlabel('s [m]')
+plt.ylabel('beta [m]')
+plt.grid(True)
+plt.show()
 }}}