MATLAB Programming

7 Working with Scientific Data Formats
Note SDgetinfo returns dimension values in row-major order, the ordering
used by HDF4. Because MATLAB stores data in column-major order, you
must specify the dimensions in column-major order, that is, [columns,rows].
In addition, you must use zero-based indexing in these arguments.
For example, to read the entire contents of a data set, use this code:
[ds_name, ds_ndims, ds_dims, ds_type, ds_atts, stat] =
hdfsd('getinfo',sds_id);
ds_start = zeros(1,ds_ndims); % Creates the vector [0 0]
ds_stride = [];
ds_edges = ds_dims;
[ds_data, status] =
hdfsd('readdata',sds_id,ds_start,ds_stride,ds_edges);
disp(ds_data)
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To read less than the entire data set, use the start, stride, and edges vectors
to specify where you want to start reading data and how much data you want
to read. For example, this code reads the entire second row of the sample
data set:
ds_start = [0 1]; % Start reading at the first column, second row
ds_stride = []; % Read each element
ds_edges = [5 1]; % Read a 1-by-5 vector of data
[ds_data, status] =
hdfsd('readdata',sds_id,ds_start,ds_stride,ds_edges);
Step 7: Closing the HDF4 Data Set. After writing data to a data set in an
HDF4 file, you must close access to the data set. In the HDF4 SD API, you
use the SDendaccess routine to close a data set. In MATLAB, use the hdfsd
function, specifying as arguments:
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