Added set_seed functionality to more interfaces.

src/sage/interfaces/magma.py

@@ -280,7 +280,8 @@ class Magma(Expect):
         sage: magma.SetDefaultRealFieldPrecision(30, nvals=0)  # optional - magma
     """
     def __init__(self, maxread=10000, script_subdirectory=None,
-                 logfile=None, server=None, server_tmpdir=None, user_config=False):
+                 logfile=None, server=None, server_tmpdir=None,
+                 user_config=False, seed=None):
         """
         INPUT:
 
@@ -331,6 +332,18 @@ def __init__(self, maxread=10000, script_subdirectory=None,
         self.__available_var = []
         self.__cache = {}
         self._preparse_colon_equals = False  # if set to try, all "=" become ":=" (some users really appreciate this)
+        self._seed = seed
+
+    def set_seed(self, seed=None):
+        """
+        Sets the seed for R interpeter.
+        The seed should be an integer.
+        """
+        if seed is None:
+            seed = self.rand_seed()
+        self.eval('SetSeed(%d)' % seed)
+        self._seed = seed
+        return seed
 
     def __reduce__(self):
         """
@@ -570,6 +583,8 @@ def _start(self):
         self.expect().expect(PROMPT)
         self.expect().expect(PROMPT)
         self.attach_spec(extcode_dir() + '/spec')
+        # set random seed
+        self.set_seed(self._seed)
 
     def set(self, var, value):
         """

src/sage/interfaces/r.py

@@ -309,9 +309,10 @@ def set_seed(self, seed=None):
 
         EXAMPLES::
 
-            r = R()
-            r.set_seed(1)
-            r.sample("1:10", 5)
+            sage: r = R()
+            sage: r.set_seed(1)
+            1
+            sage: r.sample("1:10", 5)
             [1] 3 4 5 7 2
         """
         if seed is None: