[GRASSLIST:9294] strange behavior from v.to.points : feature or bug?

[Dylan Beaudette]

Noticed something strange in v.to.points in GRASS61-CVS (current)


vector 't1' is 1000 meters long

#this should extract 11 points, each 100 meters apart
v.to.points -i in=t1 out=t1_points dmax=100

resulting table:
+------+------+------------------+
| cat  | lcat | along            |
+------+------+------------------+
|    1 |    1 |                0 |
|    2 |    1 | 90.9090909090943 |
|    3 |    1 | 181.818181818189 |
|    4 |    1 | 272.727272727283 |
|    5 |    1 | 363.636363636377 |
...
|   11 |    1 | 909.090909090943 |
|   12 |    1 | 1000.00000000004 |
+------+------+------------------+

notice that each point is about 90 meters apart, and there are 12 
points.

now when i run v.to.points with dmax=110 :
#this should extract 10 points, each 110 meters apart
v.to.points -i in=t1 out=t1_points dmax=110

resulting table:
+------+------+------------------+
| cat  | lcat | along            |
+------+------+------------------+
|    1 |    1 |                0 |
|    2 |    1 | 100.000000000004 |
|    3 |    1 | 200.000000000007 |
....
|   10 |    1 | 900.000000000034 |
|   11 |    1 | 1000.00000000004 |
+------+------+------------------+

the correct and desired result!

Any ideas on this {feature,bug} ?

Thanks,

--
Dylan Beaudette
Soils and Biogeochemistry Graduate Group
University of California at Davis
530.754.7341