Mercurial > octave-antonio
view examples/mex_demo.c @ 17118:c97a26408ee0
Implement PixelRegion option for imread().
* imread.m: document new option.
* private/__imread__.m: parse new option and set defaults.
* __magick_read__.cc (calculate region): new option to calculate the region
to be read, shifts in memory required, and output image size.
(read_indexed_images, read_images): implement reading of only specific
regions of an image.
(__magick_read__): get octave_scalar_map at start for simplicity.
author | Carnë Draug <carandraug@octave.org> |
---|---|
date | Wed, 31 Jul 2013 21:28:48 +0100 |
parents | be41c30bcb44 |
children | 877b82d73ed9 |
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// mex_demo.c -- example of a dynamically linked function for Octave. // To use this file, your version of Octave must support dynamic // linking. To find out if it does, type the command // // octave_config_info ("ENABLE_DYNAMIC_LINKING") // // at the Octave prompt. Support for dynamic linking is included if // this expression returns the string "yes". // // To compile this file, type the command // // mkoctfile mex_demo.c // // from within Octave or from the shell prompt. This will create a file // called mex_demo.mex that can be loaded by Octave. To test the mex_demo.mex // file, start Octave and type the command // // [d] = mex_demo ("easy as", 1, 2, 3) // // at the Octave prompt. Octave should respond by printing // // Hello, world! // I have 4 inputs and 1 output // d = 1.2346 // Additional samples of code are in the examples directory of the Octave // distribution. See also the chapter External Code Interface in the // documentation. #include "mex.h" // Every user function should include "mex.h" which imports the basic set of // function prototypes necessary for dynamically linked functions. In // particular, it will declare mexFunction which is used by every function // which will be visible to Octave. A mexFunction is visible in Octave under // the name of the source code file without the extension. // The four arguments to mexFunction are: // 1) The number of return arguments (# of left-hand side args). // 2) An array of pointers to return arguments. // 3) The number of input arguments (# of right-hand side args). // 4) An array of pointers to input arguments. void mexFunction (int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[]) { mexPrintf ("Hello, World!\n"); mexPrintf ("I have %d inputs and %d outputs\n", nrhs, nlhs); mxArray *v = mxCreateDoubleMatrix (1, 1, mxREAL); double *data = mxGetPr (v); *data = 1.23456789; plhs[0] = v; }