iterators and generators chapter

--HG-- rename : humansize.py => examples/humansize.py rename : roman1.py => examples/roman1.py rename : roman2.py => examples/roman2.py rename : roman3.py => examples/roman3.py rename : roman4.py => examples/roman4.py rename : roman5.py => examples/roman5.py rename : roman6.py => examples/roman6.py rename : roman7.py => examples/roman7.py rename : roman8.py => examples/roman8.py rename : romantest1.py => examples/romantest1.py rename : romantest2.py => examples/romantest2.py rename : romantest3.py => examples/romantest3.py rename : romantest4.py => examples/romantest4.py rename : romantest5.py => examples/romantest5.py rename : romantest6.py => examples/romantest6.py rename : romantest7.py => examples/romantest7.py rename : romantest8.py => examples/romantest8.py
2026-06-05 23:10:17 +00:00 · 2009-03-27 01:43:33 -05:00
parent 18b0144075
commit 933dc9459a
52 changed files with 2247 additions and 695 deletions
@@ -0,0 +1,56 @@
+"""Convert to and from Roman numerals
+
+This program is part of "Dive Into Python 3", a free Python book for
+experienced programmers.  Visit http://diveintopython3.org/ for the
+latest version.
+"""
+class OutOfRangeError(ValueError): pass
+
+roman_numeral_map = (('M',  1000),
+                     ('CM', 900),
+                     ('D',  500),
+                     ('CD', 400),
+                     ('C',  100),
+                     ('XC', 90),
+                     ('L',  50),
+                     ('XL', 40),
+                     ('X',  10),
+                     ('IX', 9),
+                     ('V',  5),
+                     ('IV', 4),
+                     ('I',  1))
+
+def to_roman(n):
+    """convert integer to Roman numeral"""
+    if not (0 < n < 4000):
+        raise OutOfRangeError("number out of range (must be 0..3999)")
+
+    result = ""
+    for numeral, integer in roman_numeral_map:
+        while n >= integer:
+            result += numeral
+            n -= integer
+    return result
+
+# Copyright (c) 2009, Mark Pilgrim, All rights reserved.
+# 
+# Redistribution and use in source and binary forms, with or without modification,
+# are permitted provided that the following conditions are met:
+# 
+# * Redistributions of source code must retain the above copyright notice,
+#   this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright notice,
+#   this list of conditions and the following disclaimer in the documentation
+#   and/or other materials provided with the distribution.
+# 
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 'AS IS'
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.