fix missing conversion to RDF

src/sage/geometry/polyhedron/cdd_file_format.py

@@ -62,6 +62,12 @@ def cdd_Vrepresentation(cdd_type, vertices, rays, lines, file_output=None):
         vertices = [[0]*ambient_dim]
         num += 1
 
+    if cdd_type is 'real':
+        from sage.rings.all import RDF
+        base_ring = RDF
+    else:
+        base_ring = None
+
     s = 'V-representation\n'
     if lines is not None:
         n = len(lines)
@@ -71,13 +77,13 @@ def cdd_Vrepresentation(cdd_type, vertices, rays, lines, file_output=None):
     s += ' ' + repr(num) + ' ' + repr(ambient_dim+1) + ' ' + cdd_type + '\n'
     if lines is not None:
         for l in lines:
-            s += ' 0 ' + _to_space_separated_string(l) + '\n'
+            s += ' 0 ' + _to_space_separated_string(l, base_ring) + '\n'
     if rays is not None:
         for r in rays:
-            s += ' 0 ' + _to_space_separated_string(r) + '\n'
+            s += ' 0 ' + _to_space_separated_string(r, base_ring) + '\n'
     if vertices is not None:
         for v in vertices:
-            s += ' 1 ' + _to_space_separated_string(v) + '\n'
+            s += ' 1 ' + _to_space_separated_string(v, base_ring) + '\n'
     s += 'end\n'
 
     if file_output is not None:
@@ -116,6 +122,12 @@ def cdd_Hrepresentation(cdd_type, ieqs, eqns, file_output=None):
     num, ambient_dim = _common_length_of(ieqs, eqns)
     ambient_dim -= 1
 
+    if cdd_type is 'real':
+        from sage.rings.all import RDF
+        base_ring = RDF
+    else:
+        base_ring = None
+
     s = 'H-representation\n'
     if eqns is not None:
         assert len(eqns)>0
@@ -126,10 +138,10 @@ def cdd_Hrepresentation(cdd_type, ieqs, eqns, file_output=None):
     s += ' ' + repr(num) + ' ' + repr(ambient_dim+1) + ' ' + cdd_type + '\n'
     if eqns is not None:
         for e in eqns:
-            s += ' ' + _to_space_separated_string(e) + '\n'
+            s += ' ' + _to_space_separated_string(e, base_ring) + '\n'
     if ieqs is not None:
         for i in ieqs:
-            s += ' ' + _to_space_separated_string(i) + '\n'
+            s += ' ' + _to_space_separated_string(i, base_ring) + '\n'
     s += 'end\n'
 
     if file_output is not None:

src/sage/geometry/polyhedron/misc.py

@@ -11,14 +11,16 @@
 # **********************************************************************
 
 
-def _to_space_separated_string(l):
+def _to_space_separated_string(l, base_ring=None):
     """
     Convert a container to a space-separated string.
 
     INPUT:
 
     - ``l`` -- anything iterable.
 
+    - ``base_ring`` -- ring (default: ``None``); convert this ring, if given
+
     OUTPUT:
 
     String.
@@ -28,7 +30,11 @@ def _to_space_separated_string(l):
         sage: import sage.geometry.polyhedron.misc as P
         sage: P._to_space_separated_string([2,3])
         '2 3'
+        sage: P._to_space_separated_string([2, 1/5], RDF)
+        '2.0 0.2'
     """
+    if base_ring:
+        return ' '.join(repr(base_ring(x)) for x in l)
     return ' '.join(repr(x) for x in l)