delete all negative numbers in a file using shell or perl

ok. I have a file like below. I want to keep all rows and columns just eliminate the values that are negative. Also, the values may sometimes be rounded to the nearest hundreth (i.e. 00.00 format) instead of just whole numbers.

02-03-2011 00:00:00 13 16 19 22 21 14 12 10 11 15 14 23 25 24 23 17 20 26 23 27 26 23 15 10
02-04-2011 00:00:00 12 18 18 14 19 4 6 6 6 8 10 12 19 17 12 7 3 3 2 0 3 3 1 1
02-05-2011 00:00:00 3 3 5 11 8 19 5 5 4 5 6 7 7 5 6 4 0 -2 -1 0 1 0 0 3
02-06-2011 00:00:00 4 4 6 4 2 2 3 3 0 0 6 8 4 5 4 3 3 0 -4 -4 1 3 3 5
02-07-2011 00:00:00 4 1 2 3 3 2 4 7 8 11 13 20 36 12 13 19 24 21 22 13 16 19 16 17
02-08-2011 00:00:00 17 15 23 27 24 19 21 13 28 22 25 25 22 23 17 4 2 3 6 21 8 10 11 12
02-09-2011 00:00:00 20 17 14 13 13 12 9 9 11 16 14 22 15 14 15 17
02-10-2011 00:00:00 15 15 22 18 13 17 9 9 9 10 7 5 7 8 8 19
02-11-2011 00:00:00 17 22 25 29 24 22 21 22 32 22 32 22 15 21 26 14 9 9 14 15 21 19 14 20
02-12-2011 00:00:00 32 30 29 24 18 23 17 14 28 27 23 31 28 27 23 23 21 19 23 21 21 28 30 28
02-13-2011 00:00:00 31 35 32 15 13 8 8 9 7 26 25 21 24 6 3 2 10 23 33 17 7 23 21 24
02-14-2011 00:00:00 23 28 28 1 0 -1 1 2 4 4 9 14 14 23 29 13 10 10 9 33 12 20 14 26
02-15-2011 00:00:00 24 17 4 8 17 11 12 12 9 9 10 10 9 7 5 4 6 5 8 16 12 22 20 19
02-16-2011 00:00:00 21 18 19 9 10 10 10 12 11 8 4 9 10 6 0 -1 -3 -3 1 2 1 -1
02-17-2011 00:00:00 0 0 0 3 2 4 9 11 12 11 12 18 19 13 10 9 17 9 12 14 13 11 11 14
02-18-2011 00:00:00 11 10 10 8 7 8 8 5 9 10 4 3 7 8 9 10 8 6 7 11 9 7 8 6
02-19-2011 00:00:00 7 10 11 13 13 13 13 11 16 17 13 22 17 16 6 8 10 11 12 13 9 6 5 2
02-20-2011 00:00:00 5 9 10 11 10 10 8 8 12 12 15 19 17 17 14 13 14 14 13 19 19 15 18 18
02-21-2011 00:00:00 12 13 6 6 11 12 18 14 15 17 27 23 18 13 9 5 2 3 4 6 9 5 4 7
02-22-2011 00:00:00 7 9 8 5 5 4 6 8 8 4 6 15 16 17 16 14 14 13 13 14 11 17 15 12
02-23-2011 00:00:00 15 7 19 8 10 10 9 7 9 13 10 10 12 12 12 10 8 5 5 11 13 12 12 9
02-24-2011 00:00:00 8 10 7 7 6 5 7 3 0 1 5 9 11 6 1 1 2 0 -2 -3 -3 -2 -1 -1
02-25-2011 00:00:00 2 3 0 1 1 -3 0 4 3 5 5 6 8 8 16 11 6 1 -3 -3 2 6 7 9
02-26-2011 00:00:00 6 3 16 3 3 4 6 8 9 10 10 8 17 8 11 9 17 8 7 4 3 6 8 10
02-27-2011 00:00:00 10 16 13 12 11 10 11 10 19 16 17 22 20 20 16 13 9 4 0 -1 1 4 8 6
02-28-2011 00:00:00 5 9 13 6 2 6 11 18 13 16 29 27 21 21 25 16 18 35 30 29 25 13 15 20
03-01-2011 00:00:00 13 17 13 18 15 13 11 12 17 21 28 27 23 21 18 21 20 19 18 7 16 22 15 15
03-02-2011 00:00:00 19 12 20 15 13 10 11 14 17 15 17 19 21 22 14 11 4 5 22 21 1 2
03-03-2011 00:00:00 19 9 8 15 10 7 3 5 10 9 9 9 2 -2 -4 -5 -5 -3 -1 -1 -5 -5 -1 -1
03-04-2011 00:00:00 -1 2 0 -3 -3 -3 -5 -4 -2 -1 -1 1 1 -1 -2 -3 -3 -1 -2 -4 -7 -7 -4 1
03-05-2011 00:00:00 4 2 2 0 -1 2 1 -5 -8 -4 -4 -1 2 5 8 6 4 3 -1 2 7 8 2 1
03-06-2011 00:00:00 2 1 -1 -3 -2 1 1 -2 -2 2 5 10 13 20 22 16 12 13 18 18 18 10 17 17
03-07-2011 00:00:00 0 2 3 21 8 9 9 9 11 10 12 18 16 12 25 19 10 7 2 3 8 12 11 17
03-08-2011 00:00:00 15 11 9 6 7 10 9 8 8 7 10 16 17 15 20 25 17 26 21 37 14 17 21 16
03-09-2011 00:00:00 25 12 12 7 9 14 17 14 14 17 12 16 21 20 25 33 29 33 42 28 18 19 30 28
03-10-2011 00:00:00 21 29 34 28 27 28 12 20 17 25 17 10 11 12 22 11 10 12 13 12 13 19 14 14
03-11-2011 00:00:00 18 13 17 4 4 17 17 11 5 5 12 11 8 9 9 9 11 16 5 8 12 10 10 11
03-12-2011 00:00:00 10 12 11 5 3 7 10 11 9 6 6 9 11 12 10 9 11 15 14 11 9 10 10 16
03-13-2011 00:00:00 15 15 7 7 8 5 3 4 6 8 7 7 7 9 9 6 0 -3 5 7 3 2 5 7
03-14-2011 00:00:00 5 2 2 7 7 5 2 2 6 6 6 8 8 7 8 9 5 0 1 3 6 6 6 9
03-15-2011 00:00:00 8 4 2 4 4 4 5 6 6 5 4 6 4 5 9 6 7 7 5 8 11 9 6 5
03-16-2011 00:00:00 7 7 6 3 0 1 3 4 5 4 4 6 9 12 11 10 11 10 4 2 2 3 1 -1
03-17-2011 00:00:00 1 0 -3 -5 -3 -3 -4 -3 1 3 2 6 7 7 8 8 8 7 3 3 5 2 -1 -1
03-18-2011 00:00:00 -1 -1 -1 1 2 3 2 1 2 1 1 6 8 10 11 8 6 7 6 2 -2 -1 1 3
03-19-2011 00:00:00 6 8 9 5 4 8 7 3 2 5 7 5 6 6 4 7 7 3 0 -1 4 5 1 2
03-20-2011 00:00:00 4 3 1 1 3 1 1 4 2 4 16 21 25 22 14 19 10 5 -2 -2 1 3 6 6