fix typo

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

diff --git a/moebius.py b/moebius.py
index 4b8d640c5240f8b04a3ecf460d4238239f925b37..16e5b2371babea62dd11fb13fa33595bdd1fbf2c 100644 (file)
--- a/moebius.py
+++ b/moebius.py
@@ -119,7 +119,7 @@ class MoebiusHalf:
     returns tuple of 4 vectors:
            - point location
            - normal (+ve is in the +ve y direction at iu=t=0) unit vector
-           - along extend   (towrds +ve iu)                   unit vector
+           - along extent   (towrds +ve iu)                   unit vector
            - along traverse (towards +ve t)                   unit vector
     '''
     if iu == m.nu: