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Code Issues Releases Activity

Make memory usage of nearfield_imager configurable

pull/1/head
Tammo Jan Dijkema 2020-02-27 20:40:48 +01:00
parent e1d1d00e3b
commit d64086c7f9
1 changed files with 4 additions and 2 deletions
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6
lofarimaging/lofarimaging.py
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@ -334,7 +334,8 @@ def ground_imager(visibilities, freq, npix_p, npix_q, dims, station_pqr, height=
return np.abs(img)
def nearfield_imager(visibilities, baseline_indices, freqs, npix_p, npix_q, extent, station_pqr, height=1.5):
def nearfield_imager(visibilities, baseline_indices, freqs, npix_p, npix_q, extent, station_pqr, height=1.5,
max_memory_mb=200):
"""
Nearfield imager
Args:
@ -346,6 +347,7 @@ def nearfield_imager(visibilities, baseline_indices, freqs, npix_p, npix_q, exte
extent: Extent (in m) that the image should span
station_pqr: PQR coordinates of stations
height: Height of image in metre
max_memory_mb: Maximum amount of memory to use for the biggest array. Higher may improve performance.
Returns:
array(float): Real-values array of shape [npix_p, npix_q]
@ -360,7 +362,7 @@ def nearfield_imager(visibilities, baseline_indices, freqs, npix_p, npix_q, exte
diff_vectors = (station_pqr[:, None, None, :] - posxyz[ None, :, :, :])
distances = np.linalg.norm(diff_vectors, axis=3)
vis_chunksize = 500
vis_chunksize = max_memory_mb * 1024 * 1024 // (8 * npix_p * npix_q)
bl_diff = np.zeros((vis_chunksize, npix_q, npix_p), dtype=np.float64)
img = np.zeros((npix_q, npix_p), dtype=np.complex128)