Modified chromaticity example for BESSY II.

Author: TeresiaOlsson

examples/BESSY2_example/BESSY2Chroma.yaml

@@ -4,11 +4,11 @@ machine: sr
 energy: 1.7e9
 simulators:
 - type: pyaml.lattice.simulator
-  lattice: bessy2.mat
+  lattice: bessy2_standard_user.mat
   name: design
 controls:
 - type: pyaml_cs_oa.controlsystem
-  prefix: 'pons:'
+  prefix: 'a3744:'
   name: live
 data_folder: /data/store
 devices:
@@ -26,10 +26,10 @@ devices:
   name: KSI
   betatron_tune: BETATRON_TUNE
   RFfreq: RF
-  fit_order: 1
+  fit_order: 2
   N_tune_meas: 1
   N_step: 5
-  Sleep_between_meas: 0
+  Sleep_between_meas: 2
   Sleep_between_RFvar: 2
   E_delta: 1e-3
   Max_E_delta: 1e-3

examples/BESSY2_example/bessy2-chroma.ipynb

@@ -0,0 +1,19 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "9be4d265",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "language_info": {
+   "name": "python"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

examples/BESSY2_example/bessy2-chroma.py

@@ -1,20 +1,44 @@
+"""Chromaticity measurement
+
+This example shows how to run chromaticity measurement using the simulator
+or the virtual accelerator.
+If you want to test the virtual accelerator you need to start the
+container before running the script.
+
+"""
+
 import numpy as np
 
 from pyaml.accelerator import Accelerator
 from pyaml.common.constants import ACTION_MEASURE
 
+# ----- Load the configuration -----
+# Remember to change the prefix for the live mode to the one matching
+# your virtual accelerator before loading.
+
+sr = Accelerator.load("BESSY2Chroma.yaml")
+
+# ----- Define a callback -----
+# This callback is used to print output during the chromaticity measurement.
+
 
 def chroma_callback(step: int, action: int, rf: float, tune: np.array):
     if action == ACTION_MEASURE:
         print(f"Chromaticy measurement: #{step} RF={rf} Tune={tune}")
     return True
 
 
-sr = Accelerator.load("BESSY2Chroma.yaml")
+# ----- Get the momentum compaction factor-----
+# To get the momentum compaction from the model you need to first turn 6D off.
+
 sr.design.get_lattice().disable_6d()
-# Retreive MCF from the model
 alphac = sr.design.get_lattice().get_mcf()
+sr.design.get_lattice().enable_6d()
 print(f"Moment compaction factor: {alphac}")
+
+# ----- Measure the chromaticity-----
+# The measurement routing will also show a plot.
+
 chromaticity_monitor = sr.live.get_chromaticity_monitor("KSI")
 chromaticity_monitor.measure(do_plot=True, alphac=alphac, callback=chroma_callback)
 ksi = chromaticity_monitor.chromaticity.get()