Add README.md

README.md

@@ -0,0 +1,102 @@
+# Virgo model
+
+Interferometer for Finesse 3. Can be used with the
+[finesse-virgo](https://gitlab.com/ifosim/finesse/finesse-virgo)
+package.
+
+Katscript files are organized by priority number (first two number),
+which indicate the file loading order, the lowest at first.
+
+## Sections
+
+Katscript files are organized in different types, which are `values`,
+`optical setup`, `link`, `cavities definition`, `degree of freedom`,
+`detectors` and `after variables`.
+
+### values
+
+priority number from 00 to 09
+
+Contains values used in the setup
+
+### optical setup
+
+priority number from 10 to 19
+
+Defined part of the optical setup (Laser, Mirror, etc.)
+
+### link
+
+priority number from 20 to 49
+
+Link parts of the optical setup defined before together
+
+### cavities
+
+priority number from 50 to 69
+
+Defines Finesse 3 cavity
+
+### degree of freedom
+
+priority number from 70 to 89
+
+Defines Finesse 3 degree of freedom
+
+### detectors
+
+priority number from 70 to 89
+
+Add Finesse 3 readout
+
+### after variables
+
+priority number from 90 to 99
+
+Defines variable which depends of components in the setup for
+preprocessing (finesse-virgo package for example)
+
+## Getting started
+
+Code example to build a Virgo model with these scripts.
+
+```py
+    virgo = Virgo(
+        files_to_parse = [
+            "00_variables.kat",
+            "01_arm_north.kat",
+            "01_arm_west.kat",
+            "01_detection.kat",
+            "01_laser_and_modulator.kat",
+            "01_recycling_cavity.kat",
+            "02_B5_path.kat",
+            "05_attenuator.kat",
+            "05_link_length.kat",
+            "05_modulation.kat",
+            "05_tuning.kat",
+            "10_laser_and_modulator.kat",
+            "10_faraday_isolator.kat",
+            "10_recycling_cavity.kat",
+            "10_arm_north.kat",
+            "10_arm_west.kat",
+            "10_detection.kat",
+            "10_B2_attenuator.kat",
+            "10_B4_attenuator.kat",
+            "25_link_laser_and_modulator_faraday_isolator_noSIB1.kat",
+            "20_link_faraday_isolator_recycling_cavity.kat",
+            "25_link_faraday_isolator_B2_attenuator_noSIB2.kat",
+            "20_link_recycling_cavity_arms.kat",
+            "25_link_recycling_cavity_detection_noSDB1.kat",
+            "25_link_recycling_cavity_B4_attenuator_noSPRB.kat",
+            "30_link_arm_north_SNEB.kat",
+            "50_cavities.kat",
+            "70_detectors.kat",
+            "70_degree_of_freedom.kat",
+            "99_after_variables.kat",
+        ],
+    )
+```
+
+The advantage of this is the control we have over the interferometer
+ simulation, and the readibility. Tracking change is also easier,
+variable definition being detached from setup configuration.