Ticket #8156: trac_8156c.patch

sage/interfaces/all.py

@@ -34 +34 @@
 from povray import povray
 from lie import lie, lie_console, LiE
 from r import r, r_console, R, r_version, is_RElement
+from read_data import read_data
 
 # signal handling 
 from get_sigs import *

new file sage/interfaces/read_data.py

@@ +1 @@
+"""
+An interface to read data files
+"""
+
+###############################################################################
+#   Sage: System for Algebra and Geometry Experimentation    
+#       Copyright (C) 2010 Paul Zimmermann
+#  Distributed under the terms of the GNU General Public License (GPL),
+#  version 2 or later. The full text of the GPL is available at:
+#                  http://www.gnu.org/licenses/
+###############################################################################
+
+def read_data(f,t):
+   r"""
+   Read data from file 'f' and class 't' (one element per line),
+   and returns a list of elements.
+
+   INPUT:
+
+       - 'f' - a file name
+       - 't' - a class (objects will be coerced to that class)
+
+   OUTPUT:
+
+       a list of elements of class 't'.
+
+   EXAMPLES::
+
+       sage: indata = tmp_filename()
+       sage: f = open(indata, "w")
+       sage: f.write("17\n42\n")
+       sage: f.close()
+       sage: l = read_data(indata, ZZ); l
+       [17, 42]
+       sage: f = open(indata, "w")
+       sage: f.write("1.234\n5.678\n")
+       sage: f.close()
+       sage: l = read_data(indata, RealField(17)); l
+       [1.234, 5.678]
+   """
+   fp = open(f,"r")
+   l = []
+   while True:
+      s = fp.readline()
+      s = s.rstrip()
+      if s == '':
+         break
+      l.append(t(s))
+   fp.close()
+   return l