Update README

README.md

@@ -3,5 +3,47 @@
 Collection of scripts to run analysis of LST data at the IT cluster in La Palma.
 The repository contains also a folder with some bash scripts that can be easily used.
 
+## Analysis tree
+
+Use `create_analysis_tree.py` to create automatically a directory tree.
+The default one is:
+
+```bash
+Parent_Folder
+        └──DL1
+            ├── source
+            │   └── night
+            │      └── version
+            │           └── cleaning
+            DL2
+            ├── source
+            │   └── night
+            │      └── version
+            │           └── cleaning
+            DL3
+            └── source
+                └── night
+                   └── version
+                        └── cleaning
+```
+
+Modify the script at your convenience if you prefer a different structure.
+Change the default value for the Parent folder in the argparse with your own path.
+
+Example:
+
+```bash
+python create_analysis_tree.py --source Crab --night 20220304
+```
+
+Output:
+
+```bash
+Directory  /fefs/aswg/workspace/alice.donini/Analysis/data/DL1/Crab/20220304/v0.9.2/tailcut84  already exists
+Directory  /fefs/aswg/workspace/alice.donini/Analysis/data/DL2/Crab/20220304/v0.9.2/tailcut84  Created
+Directory  /fefs/aswg/workspace/alice.donini/Analysis/data/DL3/Crab/20220304/v0.9.2/tailcut84  Created
+Directory structure ready for analysis on Crab.
+```
+
 ## Contributing
 Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.
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