This example uses basic sampling to select two samples of five rows each, weighted by car weight. Because the function call includes the Seed and SeedColumn syntax elements, it always produces the same output from the same input.
Input
The input table, fs_input, has 32 observations of 11 variables for different models of cars. The variables vs and am are categorical; the others are numerical.
Variable | Description |
---|---|
mpg | Miles per U. S. gallon |
cyl | Number of cylinders |
disp | Displacement (cubic inches) |
hp | Gross horsepower |
drat | Drive ratio |
wt | Weight (lbs/1000) |
qsec | Quarter-mile time (seconds) |
vs | Engine configuraton (V or S (straight)) |
am | Transmission type (automatic or manual) |
gear | Number of forward gears |
carb | Number of carburetors |
sn | model | mpg | cyl | disp | hp | drat | wt | qsec | vs | am | gear | carb |
---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Mazda RX4 | 21 | 6 | 160 | 110 | 3.9 | 2.62 | 16.46 | S | manual | 4 | 4 |
2 | Mazda RX4 Wag | 21 | 6 | 160 | 110 | 3.9 | 2.875 | 17.02 | S | manual | 4 | 4 |
3 | Datsun 710 | 22.8 | 4 | 108 | 93 | 3.85 | 2.32 | 18.61 | V | manual | 4 | 1 |
4 | Hornet 4 Drive | 21.4 | 6 | 258 | 110 | 3.08 | 3.215 | 19.44 | V | automatic | 3 | 1 |
5 | Hornet Sportabout | 18.7 | 8 | 360 | 175 | 3.15 | 3.44 | 17.02 | S | automatic | 3 | 2 |
6 | Valiant | 18.1 | 6 | 225 | 105 | 2.76 | 3.46 | 20.22 | V | automatic | 3 | 1 |
7 | Duster 360 | 14.3 | 8 | 360 | 245 | 3.21 | 3.57 | 15.84 | S | automatic | 3 | 4 |
8 | Merc 240D | 24.4 | 4 | 146.7 | 62 | 3.69 | 3.19 | 20 | V | automatic | 4 | 2 |
9 | Merc 230 | 22.8 | 4 | 140.8 | 95 | 3.92 | 3.15 | 22.9 | V | automatic | 4 | 2 |
10 | Merc 280 | 19.2 | 6 | 167.6 | 123 | 3.92 | 3.44 | 18.3 | V | automatic | 4 | 4 |
11 | Merc 280C | 17.8 | 6 | 167.6 | 123 | 3.92 | 3.44 | 18.9 | V | automatic | 4 | 4 |
12 | Merc 450SE | 16.4 | 8 | 275.8 | 180 | 3.07 | 4.07 | 17.4 | S | automatic | 3 | 3 |
13 | Merc 450SL | 17.3 | 8 | 275.8 | 180 | 3.07 | 3.73 | 17.6 | S | automatic | 3 | 3 |
14 | Merc 450SLC | 15.2 | 8 | 275.8 | 180 | 3.07 | 3.78 | 18 | S | automatic | 3 | 3 |
15 | Cadillac Fleetwood | 10.4 | 8 | 472 | 205 | 2.93 | 5.25 | 17.98 | S | automatic | 3 | 4 |
16 | Lincoln Continental | 10.4 | 8 | 460 | 215 | 3 | 5.424 | 17.82 | S | automatic | 3 | 4 |
17 | Chrysler Imperial | 14.7 | 8 | 440 | 230 | 3.23 | 5.345 | 17.42 | S | automatic | 3 | 4 |
18 | Fiat 128 | 32.4 | 4 | 78.7 | 66 | 4.08 | 2.2 | 19.47 | V | manual | 4 | 1 |
19 | Honda Civic | 30.4 | 4 | 75.7 | 52 | 4.93 | 1.615 | 18.52 | V | manual | 4 | 2 |
20 | Toyota Corolla | 33.9 | 4 | 71.1 | 65 | 4.22 | 1.835 | 19.9 | V | manual | 4 | 1 |
21 | Toyota Corona | 21.5 | 4 | 120.1 | 97 | 3.7 | 2.465 | 20.01 | V | automatic | 3 | 1 |
22 | Dodge Challenger | 15.5 | 8 | 318 | 150 | 2.76 | 3.52 | 16.87 | S | automatic | 3 | 2 |
23 | AMC Javelin | 15.2 | 8 | 304 | 150 | 3.15 | 3.435 | 17.3 | S | automatic | 3 | 2 |
24 | Camaro Z28 | 13.3 | 8 | 350 | 245 | 3.73 | 3.84 | 15.41 | S | automatic | 3 | 4 |
25 | Pontiac Firebird | 19.2 | 8 | 400 | 175 | 3.08 | 3.845 | 17.05 | S | automatic | 3 | 2 |
26 | Fiat X1-9 | 27.3 | 4 | 79 | 66 | 4.08 | 1.935 | 18.9 | V | manual | 4 | 1 |
27 | Porsche 914-2 | 26 | 4 | 120.3 | 91 | 4.43 | 2.14 | 16.7 | S | manual | 5 | 2 |
28 | Lotus Europa | 30.4 | 4 | 95.1 | 113 | 3.77 | 1.513 | 16.9 | V | manual | 5 | 2 |
29 | Ford Pantera L | 15.8 | 8 | 351 | 264 | 4.22 | 3.17 | 14.5 | S | manual | 5 | 4 |
30 | Ferrari Dino | 19.7 | 6 | 145 | 175 | 3.62 | 2.77 | 15.5 | S | manual | 5 | 6 |
31 | Maserati Bora | 15 | 8 | 301 | 335 | 3.54 | 3.57 | 14.6 | S | manual | 5 | 8 |
32 | Volvo 142E | 21.4 | 4 | 121 | 109 | 4.11 | 2.78 | 18.6 | V | manual | 4 | 2 |
SQL Call
SELECT * FROM RandomSample( ON fs_input AS InputTable USING SamplingMode ('basic') NumSample(5,5) WeightColumn('wt') Seed(1) SeedColumn('model') ) AS dt ORDER BY 1,2,3;
Output
set_id sn model mpg cyl disp hp drat wt qsec vs am gear carb ------ -- ------------------- ---- --- ----- ----- ---- ----- ----- -- --------- ---- ---- 0 1 mazda rx4 21.0 6 160.0 110.0 3.9 2.62 16.46 s manual 4 4 0 13 merc 450sl 17.3 8 275.8 180.0 3.07 3.73 17.6 s automatic 3 3 0 14 merc 450slc 15.2 8 275.8 180.0 3.07 3.78 18.0 s automatic 3 3 0 16 lincoln continental 10.4 8 460.0 215.0 3.0 5.424 17.82 s automatic 3 4 0 28 lotus europa 30.4 4 95.1 113.0 3.77 1.513 16.9 v manual 5 2 1 11 merc 280c 17.8 6 167.6 123.0 3.92 3.44 18.9 v automatic 4 4 1 15 cadillac fleetwood 10.4 8 472.0 205.0 2.93 5.25 17.98 s automatic 3 4 1 17 chrysler imperial 14.7 8 440.0 230.0 3.23 5.345 17.42 s automatic 3 4 1 25 pontiac firebird 19.2 8 400.0 175.0 3.08 3.845 17.05 s automatic 3 2 1 32 volvo 142e 21.4 4 121.0 109.0 4.11 2.78 18.6 v manual 4 2
Download a zip file of all examples and a SQL script file that creates their input tables.