6. ACKNOLEWGEMENTS
The authors would like to thank the GRASS Information A special thank also to Ennio Pozzetti for the precious
Center and Research Group and the Postgres Group. suggestions.
Test
N
Regioi
S
i limits
W
E
Extrac
Postgres
ion poin
Grass
ts times (sec)
Postgres/Grass
Points number
A1
36.1167
34.5167
16.8083
18.4083
0.14
0.01
14
368
A2
42.5167
40.9167
12.0083
13.6083
0.13
0.01
13
368
A3
48.9167
47.3167
4.0833
5.6083
0.15
0.01
15
368
B1
37.7167
34.5167
16.8083
20.0083
0.22
0.01
22
1472
B2
44.1167
40.9167
12.0083
15.2083
0.22
0.01
22
1472
B3
48.9167
45.7167
4.0833
7.2083
0.21
0.01
21
1472
C1
48.9167
44.1167
5.6083
10.4083
0.35
0.01
35
3312
C2
44.1167
39.3167
10.4083
15.2083
0.34
0.01
34
3312
C3
39.3167
34.5167
15.2083
20.0083
0.34
0.01
34
3312
D1
44.1167
37.7167
8.8083
15.2083
0.51
0.01
51
5888
E1
44.1167
36.1167
8.8083
16.8083
0.72
0.01
72
9200
F1
45.7167
36.1167
7.2083
16.8083
1.00
0.01
100
13248
G1
48.9167
34.0833
4.0833
20.9167
2.50
0.01
250
36134
Table 4 - Tests performed on the raster file DTMLARGO
Test
Region limits
Extraction points times (sec)
Points number
N
s
W
E
Postgres
Grass
Postgres/Grass
A1
37.716
36.116
13.608
15.208
2.3
15.9
0.145
15767
A2
42.516
40.916
12.008
13.608
2.1
15.7
0.134
8914
A3
45.716
44.116
5.608
7.208
0.3
15.5
0.019
390
A4
45.716
44.116
10.4081
12.008
4.7
15.8
0.297
24032
A5
42.516
40.916
13.608
15.208
4.4
16.1
0.273
29704
A6
40.916
39.316
8.809
10.408
0.4
14.9
0.027
1804
B1
39.316
36.116
13.608
16.908
3.2
15.5
0.206
25027
B2
44.116
40.916
12.008
15.208
6.9
16.4
0.421
58512
B3
47.316
44.116
5.608
8.808
3.8
15.3
0.248
16857
B4
40.916
37.716
7.208
10.408
0.8
15
0.053
3918
C1
40.916
36.116
12.008
16.808
7.2
16.4
0.439
63367
C2
47.316
42.516
5.608
10.408
5.3
15.9
0.333
40111
C3
47.316
42.516
10.408
15.208
8.5
16.6
0.512
72043
C4
42.516
37.716
7.208
12.008
0.8
14.9
0.054
5014
D1
47.316
40.916
5.608
12.008
9.9
17
0.582
81650
D2
42.516
36.116
12.008
18.408
13.6
18
0.756
127237
D3
42.516
36.116
5.608
12.008
0.7
15
0.047
5020
D4
47.316
40.916
10.408
16.908
14
18.2
0.769
125025
E1
47.316
39.316
/.208
15.208
17.4
18.9
0.921
161466
F1
47.316
37.716
7.208
16.808
22
20.5
1.073
213602
G1
48.916
34.083
4.083
20.916
34
21.6
1.574
244708
Table 5 - Tests performed on the site points file ITALGRAV
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