sample [ parameter=value ... ] [ inputfile outputfile ] sample [ parameter=value ... ] [ inputfile ... directory ]
Parameters are: point_file, points_are, include_vars, output_coords.
sample takes one or more input datasets and samples them using the list of points in a point_file dataset. One output file is created for each input file. The contents of the point_file and the method of sampling are based on the specification of the parameter points_are as follows:
1) points - requires a 1-D dataset of (x, y) or (lat, lon) pairs. The list can be any dimension and the variables must be named (x, y) or (latitude, longitude), respectively. The input datasets are sampled at the locations nearest to the points specified in the list.
2) vectors - requires a 1-D dataset of (x, y, delta_x, delta_y) or (lat, lon, delta_lat, delta_lon) values. The list can be any dimension and the variables must be named (x, y, delta_x, delta_y) or (latitude, longitude, delta_lat, delta_lon), respectively. The input datasets are sampled at the locations nearest the points along the specified vectors.
3) tracks - requires a 1-D dataset of (x, y) or (lat, lon) pairs. The list can be any dimension and the variables must be named (x, y) or (latitude, longitude), respectively. The list is interpreted to represent one or more sequences of points (one or more tracks). Points in the list made up of bad_values (see datasets) delimit tracks; i.e., the previous track is ended and the next point starts a new track. The input datasets are sampled at the locations nearest to the points along the specified tracks.
4) outlines - requires a 1-D dataset of (x, y) or (lat, lon) pairs. The list can be any dimension and the variables must be named (x, y) or (latitude, longitude), respectively. The list is interpreted to represent one or more connected regions (or polygons). Points in the list made up of bad_values (see datasets) delimit polygons; i.e., the previous region being outlined is closed and the next point starts a new polygon. The input datasets are sampled at all locations insided the outlined region.
5) boxes - requires a 1-D dataset of (x, y, delta_x, delta_y) or (lat, lon, delta_lat, delta_lon) values. The list can be any dimension and the variables must be named (x, y, delta_x, delta_y) or (latitude, longitude, delta_lat, delta_lon), respectively. Each point in the list is interpreted to represent two opposite corners of a rectangle. The input datasets are sampled at all locations inside the rectangles.
If a dataset has dimensions x, y and z and the sampling is done in the x and y dimensions, the output dataset retains the z dimension of the data.
All input datasets are assumed to have line and sample or latitude and longitude dimensions. They are also assumed to have the same variable names, datatype, bad value, units, and scaling as the first input dataset. An error is returned if the variable names, size of the dimensions, or datatype do not all match. If latitude and longitude format is used for specifying points, each dataset must have the same earth transform.
This is the name of the TeraScan dataset containing the 1-D set of points (see descriptions above).
There is no default.
Specifies the sampling method (see descriptions above).
Valid responses are [ points, vectors, tracks, outlines, boxes ]. The default is points.
Specifies which variables in the input dataset(s) to sample and write to the output datasets. If this list is prefixed with a minus sign, all variables, except those listed, will be sampled. Wildcards * and ? are allowed.
The default is all variables in the input dataset(s).
If output_coords=yes, sample writes the x, y or lat,lon coordinates where the samples were taken to the output file. In the case of points_are=points, the information is the same as in the point_file, although for the other cases, the sample locations are generated internally and thus it may be necessary to keep the generated list of sample points.
The default is no.
lapaz% sample in/out files : char(255) ? n11.93206.2334 n11.sample point_file : char(255) ? n11.points points_are : char( 8) ? [points] include_vars : char(255) ? [] avhrr_ch3 output_coords : char( 3) ? [no] yes lapaz%
datasets, samplam, laminate, dimavg, formats.
Last Update: $Date: 1998/05/29 20:42:31 $