Update README.md

Author: Landon Clipp

README.md

@@ -1 +1,31 @@
-# batch4py
+# batch4py
+
+batch4py is a lightweight Python module that provides a programmatic interface to many common High Performance Computing (HPC) batch schedulers. It also provides a simple way to define directed acyclic graphs (DAG) of job chains.
+
+A common workflow to submit jobs on a batch scheduler looks something like this:
+
+```
+$ qsub job1.pbs  
+$ qsub -W afterany:8625371 job2.pbs  
+$ qsub -W afterany:8625371 job3.pbs  
+$ qsub -W afterany:8625372 job4.pbs  
+```
+
+Performing these steps manually is fine for a handful of jobs, but doing it for dozens or hundreds of jobs becomes impractical. A 100-batch job looks like this in batch4py:
+
+```
+job_list = []  
+chain = batch4py.JobChain( 'pbs' )
+for i in range(100):
+    new_job = batch4py.Job( list_of_job_files[i] )
+    job_list.append( new_job )
+    chain.add_job( job_list[i] )
+    
+# Define a simple linear tree
+for i in range(99):
+    chain.set_dep( job_list[i], job_list[i+1], 'afterany' )
+    
+# Submit job chain
+chain.submit()
+```
+