Edit make banksim to allow external injection file (#4808)

* functionality to use external inj.xml file in pycbc_make_banksim

* updating docs to add the new functionality of using external inj.xml file

* Fixing formatting issue

bin/pycbc_make_banksim

@@ -185,8 +185,19 @@ shutil.copy(banksim_prog, 'scripts/pycbc_banksim')
 os.chmod('scripts/pycbc_banksim', 0o0777)
 
 logging.info("Creating injection file")
-inj_str = "lalapps_inspinj " + get_ini_opts(confs, "inspinj") + "--output inj.xml"
-os.system(inj_str)
+if confs.has_section("inspinj"):
+    logging.info("Using lalapps_inspinj to create injections")
+    inj_str = "lalapps_inspinj " + get_ini_opts(confs, "inspinj") + "--output inj.xml"
+    os.system(inj_str)
+elif confs.has_section("external_injection"):
+    logging.info("Using external injection file. Please ensure the file is in sim_inspiral table (.xml) format.")
+    inj_file_path = confs.get("external_injection", "inj-file")
+    if inj_file_path == "inj.xml":
+        pass
+    else:
+        os.system("cp {} inj.xml".format(inj_file_path))
+else:
+    raise ValueError("Need to specify the injection method. Either provide [inspinj] section or [external_injection]")
 
 logging.info("Splitting template bank")
 subprocess.call(['pycbc_splitbank',

docs/banksim.rst

@@ -26,7 +26,7 @@ Below is an example.
 
 .. literalinclude:: ../examples/banksim/banksim_simple.ini
 
-There are four sections that must be present [inspinj], [executables], [workflow],
+There are four sections that must be present [inspinj]/[external_injection], [executables], [workflow],
 and [banksim].
 
  #. inspinj
@@ -41,6 +41,17 @@ and [banksim].
     determine the actual approximants that will be compared. That is set in the [banksim] 
     section. 
 
+    If you want to use another method to create injections (Eg. ``pycbc_create_injections``), 
+    instead of using [inspinj], you can name the section [external_injection] and specify the 
+    path of the injection file. 
+
+    .. code-block:: bash
+
+        [external_injection]
+        inj-file = /path/to/inj.xml
+
+    Note: The injection file should be in the sim_inspiral table (.xml) format.
+
  #. executables
 
     This section lists the location of the pycbc_banksim script. Make note
@@ -61,7 +72,7 @@ and [banksim].
     has to calculate fitting factors for. 
 
     The injection
-    file generated from the [inspinj] section is split
+    file generated from the [inspinj] section or provided externally is split
     into smaller pieces to satisfy this requirement.
     Note that this option has a direct effect on the memory
     requirements of each banksim job, as each injection