=== modified file 'madgraph/core/base_objects.py'
--- madgraph/core/base_objects.py	2013-11-29 07:28:53 +0000
+++ madgraph/core/base_objects.py	2014-02-18 12:35:08 +0000
@@ -1585,9 +1585,9 @@
     which should be define in the param_card.dat"""
     
     depend = ('external',)
-    type = 'real'
+#    type = 'real'
     
-    def __init__(self, name, value, lhablock, lhacode):
+    def __init__(self, name, value, lhablock, lhacode,type='real'):
         """Initialize a new ParamCardVariable
         name: name of the variable
         value: default numerical value
@@ -1598,6 +1598,7 @@
         self.value = value 
         self.lhablock = lhablock
         self.lhacode = lhacode
+        self.type = type
 
 
 #===============================================================================

=== modified file 'madgraph/interface/common_run_interface.py'
--- madgraph/interface/common_run_interface.py	2014-02-05 23:28:12 +0000
+++ madgraph/interface/common_run_interface.py	2014-02-18 15:50:39 +0000
@@ -1826,12 +1826,16 @@
                     self.setP(args[start], key, args[-1])   
                 else:
                     try:
-                        value = float(args[-1])
+                        value = complex(args[-1])
+                        valueformat = 'complex'
+                        if value.imag == 0.:
+                        	value = value.real
+                        	valueformat = 'float'
                     except Exception:
                         logger.warning('Invalid input: Expected number and not \'%s\'' \
                                                                      % args[-1])
                         return
-                    self.setP(args[start], key, value)
+                    self.setP(args[start], key, value, format=valueformat)
             else:
                 logger.warning('invalid set command %s' % line)
                 return
@@ -1858,7 +1862,7 @@
         logger.info('modify parameter %s of the run_card.dat to %s' % (name, value))
         self.run_card[name] = value
         
-    def setP(self, block, lhaid, value):
+    def setP(self, block, lhaid, value, format='float'):
         if isinstance(value, str):
             value = value.lower()
             if value == 'default':
@@ -1872,12 +1876,17 @@
                     return
             else:
                 try:
-                    value = float(value)
+                    value = complex(value)
+                    format = 'complex'
+                    if value.imag == 0.:
+                    	value = float(value.real)
+                    	format = 'float'
                 except ValueError:
                     logger.warning('Invalid input: \'%s\' not valid intput.'% value)
                     
-        logger.info('modify param_card information BLOCK %s with id %s set to %s' %\
-                    (block, lhaid, value))
+        logger.info('modify param_card information BLOCK %s with id %s set to %s with type %s' %\
+                    (block, lhaid, value, format))
+        self.param_card[block].param_dict[lhaid].format = format
         self.param_card[block].param_dict[lhaid].value = value
         
       

=== modified file 'madgraph/iolibs/export_v4.py'
--- madgraph/iolibs/export_v4.py	2014-01-08 09:16:49 +0000
+++ madgraph/iolibs/export_v4.py	2014-02-18 12:36:40 +0000
@@ -3703,6 +3703,10 @@
                             self.params_indep if param.type == 'complex' and
                             is_valid(param.name)]
 
+        complex_parameters += [param.name for param in self.params_ext 
+                            if param.type == 'complex' and
+                            is_valid(param.name)]
+        
         if complex_parameters:
             fsock.writelines('double complex '+','.join(complex_parameters)+'\n')
             fsock.writelines('common/params_C/ '+','.join(complex_parameters)+'\n\n')

=== modified file 'models/check_param_card.py'
--- models/check_param_card.py	2014-01-29 15:48:36 +0000
+++ models/check_param_card.py	2014-02-18 15:53:44 +0000
@@ -24,7 +24,6 @@
     def __init__(self, param=None, block=None, lhacode=None, value=None, comment=None):
         """Init the parameter"""
 
-        self.format = 'float'
         if param:
             block = param.lhablock
             lhacode = param.lhacode
@@ -37,7 +36,13 @@
             self.lhacode = lhacode
         else:
             self.lhacode = []
-        self.value = value
+        if value:
+            if value.imag == 0.:
+                self.format = 'float'
+                self.value = float(value.real)
+            else:
+                self.format = 'complex'
+                self.value = complex(value)
         self.comment = comment
 
     def set_block(self, block):
@@ -67,7 +72,11 @@
         
         # convert to number when possible
         try:
-            self.value = float(self.value)
+             self.value = complex(self.value)
+             self.format = 'complex'
+             if self.value.imag == 0.0:
+                 self.value = float(self.value.real)
+                 self.format = 'float'
         except:
             self.format = 'str'
             pass
@@ -117,6 +126,8 @@
             return '      %e %s # %s' % ( self.value,' '.join([str(d) for d in self.lhacode]), self.comment)
         elif self.format == 'int':
             return '      %s %i # %s' % (' '.join([str(d) for d in self.lhacode]), int(self.value), self.comment)
+        elif self.format == 'complex':
+            return '      %s (%e, %e) # %s' % (' '.join([str(d) for d in self.lhacode]), self.value.real, self.value.imag, self.comment)
         else:
             if self.lhablock == 'decay':
                 return 'DECAY %s %d # %s' % (' '.join([str(d) for d in self.lhacode]), self.value, self.comment)

=== modified file 'models/import_ufo.py'
--- models/import_ufo.py	2013-12-17 23:25:28 +0000
+++ models/import_ufo.py	2014-02-18 12:39:52 +0000
@@ -884,7 +884,7 @@
         for param in self.model.all_parameters:
             if param.nature == 'external':
                 parameter = base_objects.ParamCardVariable(param.name, param.value, \
-                                               param.lhablock, param.lhacode)
+                                               param.lhablock, param.lhacode, type=param.type)
                 
             else:
                 expr = self.shorten_expr(param.value)

=== modified file 'models/model_reader.py'
--- models/model_reader.py	2014-01-03 09:28:21 +0000
+++ models/model_reader.py	2014-02-18 12:58:24 +0000
@@ -137,7 +137,7 @@
                             value = runner(scale)
                         exec("locals()[\'%s\'] = %s" % (parameter_dict[block][id].name,
                                           value))
-                        parameter_dict[block][id].value = float(value)
+                        parameter_dict[block][id].value = complex(value)
            
         else:
             # No param_card, use default values