Support parameter substitutions

README.md

@@ -101,7 +101,7 @@ parameter file that you should correct before submitting to the cluster.
 The example below includes documentation of each parameter, and can be
 used as a starting point for your own parameter files
 
-```yaml
+``` yaml
 
 # The command to run, including any arguments that always stay the same,
 # and will not be explored by the runner.
@@ -162,7 +162,7 @@ time_limit: 3-00:00
 #
 # For each parameter the following properties are required:
 #
-#    type:  'int_range'        A range of integers -or-
+#    type: 'int_range'        A range of integers -or-
 #           'real_range'       A range of real numbers -or-
 #           'choice'           A list of string options
 #
@@ -172,6 +172,10 @@ time_limit: 3-00:00
 #    flag: '--example'        A flag which should proceed the value of the paremeter
 #    optional: true           If true, we consider combinations excluding this parameter
 #
+#    substitution: '%1'       If substitution is specfied, the parameter value
+#    optional: true           will replace the placeholder supplied in the
+#                             command, instead of being appended to the command
+#
 #  int_range and real_range types take paremeters:
 #
 #     min: 10                 Minimum value for the parameter
@@ -230,4 +234,4 @@ parameters:
       - sigmoid
     description: Activation function
 
-```
\ No newline at end of file
+```

param_runner/param.py

@@ -236,11 +236,13 @@ class ParamFile(object):
         current_param = params[param_idx]
         current_id = current_param['id']
         current_flag = current_param.get('flag', None)
+        current_sub  = current_param.get('substitution', None)
         num_values = len(current_param['range'])
 
         for val_idx in range(num_values):
             current_value = current_param['range'][val_idx]
             current_combination[current_id] = {'flag': current_flag,
+                                               'substitution': current_sub,
                                                'value': current_value}
             all_combinations = self.__recurse_arg_combns(param_idx + 1,
                                                          deepcopy(
@@ -264,11 +266,19 @@ class ParamFile(object):
 
         for arg in arg_combn.values():
 
-            if arg['flag'] and arg['value'] is not None:
-                cmd_str += arg['flag'] + ' '
 
-            if arg['value'] is not None:
-                cmd_str += str(arg['value']) + ' '
+            # In substitution mode we replace a placeholder in the command string
+            if arg['substitution'] is not None:
+                cmd_str = cmd_str.replace(arg['substitution'], arg['value'])
+
+            # Otherwise we append args, possibly prefixed with specified flags
+            else:
+
+                if arg['flag'] and arg['value'] is not None:
+                    cmd_str += arg['flag'] + ' '
+
+                if arg['value'] is not None:
+                    cmd_str += str(arg['value']) + ' '
 
         return cmd_str.rstrip(' ')
 

param_runner/schema/param_runner.jsonschema.yml

@@ -132,6 +132,9 @@
                 },
                 "description":{
                     "type":"string"
+                },
+                "substitution":{
+                    "type":"string"
                 }
             },
             "required":[
@@ -174,6 +177,9 @@
                 },
                 "description":{
                     "type":"string"
+                },
+                "substitution":{
+                    "type":"string"
                 }
             },
             "required":[
@@ -211,6 +217,9 @@
                 },
                 "description":{
                     "type":"string"
+                },
+                "substitution":{
+                    "type":"string"
                 }
             },
             "required":[