updated

README.rst

@@ -32,12 +32,45 @@ To install::
 That will install the templates with the code.  Alternatively, the templates
 can be put elsewhere and set ``$RR_TEMPLATE_DIR`` to that location.
 
-Running
--------
+Users are recommended to see details of `rrdesi` before running `redrock` to understand the      arguments in more details.
+
+Run::
+    
+    rrdesi --help
+
+Running Redrock on desi spectra
+-------------------------------
+
+**1) Without Archetypes**::
+
+    rrdesi -i <spectra_file> --output <output_file> --details <details_file.h5> -n 1
+
+**2) With Archetypes**::
+    
+In archetype mode, redrock can be run either with one particular archetype file (e.g., GALAXY, QSO or STAR) or you can also provide the full directory that contains archetypes for all spectypes.
+
+You can also define your own set of archetypes, however users must follow the file structure of redrock-archetypes. To start with, user should clone following repository to run redrock in Archetype mode::
+    
+    git clone https://github.com/abhi0395/new-archetypes.git
+
+Or::
+
+    git clone https://github.com/desihub/redrock-archetypes.git
+
+Example run::
+    
+    rrdesi -i <spectra_file> --archetypes <archetype_dir or archetype_file> --output <output_file> --details <details_file.h5> -deg_legendre 2 --nminima 9
+
+**3) Archetypes + Nearest neighbours (in chi2 space) approach**::
+
+Similar to archetypes (method - 2) but also looks for the nearest neighbours of the bestarchetypes in chi2 space. Then uses a combination of those nearest neighbours and Legendre polynomials to fit the galaxy spectra using bounded value least square method.
+
+Example run ::
+        
+    rrdesi -i <spectra_file> --archetypes <archetype_dir or archetype_file> -o <output_file> -d  <details_file.h5> -deg_legendre 2 -n_nearest 2
 
-To run on desi bricks files::
+For comment or help regarding archetypes please contact AbhijeetAnand [at] lbl.gov
 
-    rrdesi --zbest zbest.fits --output rrdetails.h5 brick*.fits
 
 License
 -------