1 /*
2  * Copyright (c) 2016-2017, The University of Oxford
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14  *    software without specific prior written permission.
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28 
29 #ifndef OSKAR_IMAGER_ROTATE_VIS_H_
30 #define OSKAR_IMAGER_ROTATE_VIS_H_
31 
32 /**
33  * @file oskar_imager_rotate_vis.h
34  */
35 
36 #include <oskar_global.h>
37 #include <mem/oskar_mem.h>
38 #include <stddef.h>
39 
40 #ifdef __cplusplus
41 extern "C" {
42 #endif
43 
44 /**
45  * @brief
46  * Performs visibility amplitude phase rotation to a new phase centre.
47  *
48  * @details
49  * This function performs visibility amplitude phase rotation to a new phase
50  * centre.
51  *
52  * Prior to calling this function, the new phase centre must be set first
53  * using oskar_imager_set_direction(), and then the original phase centre
54  * must be set using oskar_imager_set_vis_phase_centre().
55  * Note that the order of these function calls is important.
56  *
57  * Note that the coordinates (uu_in, vv_in, ww_in) correspond to the original
58  * phase centre, and must be in wavelengths.
59  *
60  * Reference:
61  * Cornwell, T.J., & Perley, R.A., 1992,
62  * "Radio-interferometric imaging of very large fields"
63  *
64  * @param[in] h             Handle to imager.
65  * @param[in] num_vis       Number of visibilities.
66  * @param[in] uu_in         Original baseline UU coordinates, in wavelengths.
67  * @param[in] vv_in         Original baseline VV coordinates, in wavelengths.
68  * @param[in] ww_in         Original baseline WW coordinates, in wavelengths.
69  * @param[in,out] amps      Complex visibility amplitudes.
70  */
71 OSKAR_EXPORT
72 void oskar_imager_rotate_vis(oskar_Imager* h, size_t num_vis,
73         const oskar_Mem* uu_in, const oskar_Mem* vv_in, const oskar_Mem* ww_in,
74         oskar_Mem* amps);
75 
76 #ifdef __cplusplus
77 }
78 #endif
79 
80 #endif /* OSKAR_IMAGER_ROTATE_VIS_H_ */
81