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The module insert_point_sources_in_sky.py currently splits evenly the polarized flux between Q and U. Actually one can use the polarization angle information available in the catalog to calculate the Q and U intensities

The NaMaster package can not be installed automatically, its dependencies (such as numpy or required binary libraries) need to be installed beforehand. This package needs to be installed independently from qubic.

The issue relates to insert_point_source_in_sky.py. Ideally it should work on a list of sources but as a matter of fact it adds only the last source in the list.

Should include FGBuster dependency.

The packages required to build qubicsoft should be specified in the pyproject.toml file.

The 2d cartesian communicator of the acquisition was used in some places to get the total number of detectors and samplings. The correct communicators are the instrument.detector and sampling communicators.

By default, the conda create in the README file should have the python version needed:
conda create --yes --name venv-qubic python==3.xx

Nosetests being discontinued, the tests need to be converted to pytests. They also need to be updated, since the change involving using dictionary as an argument to QubicInstrument, QubicAcquisition etc. broke them.

The default value for the compress parameter to write_map is True, meaning that the code will use one of the compression algorithms specified by the FITS standard. Since these algorithms are lossy when applied to maps containing floating-point values, the code will silently introduce an error in the data written to disk, as the following example shows:

import numpy
import qubic.io

FILE_NAME = '/tmp/compressed_map.fits'

INPUT_PIXELS = numpy.random.normal(size=12 * 64 * 64)
qubic.io.write_map(FILE_NAME, INPUT_PIXELS, dtype=numpy.float64)
OUTPUT_PIXELS = qubic.io.read_map(FILE_NAME)

DIFF = OUTPUT_PIXELS - INPUT_PIXELS
print('Stddev of the difference: {0:.3f}'
      .format(numpy.std(DIFF)))

# Result:
# Stddev of the difference: 0.018

(Note that the code uses float64 instead of the default float32 type when calling write_map.) Setting compress=False in the above call to qubic.io.write_map makes the difference between INPUT_PIXELS and OUTPUT_PIXELS to vanish.

Since this behaviour might be surprising for people not versed with the FITS standard, I am suggesting a couple of workarounds:

1. Make compress default to False, and specify in the docstring for write_map that using True with floating-point maps will introduce an error in the pixel values (currently, the docstring does not mention the compress parameter anywhere but in the declaration);
2. Make the code emit a warning when compress is True and the datatype of the parameter map is a floating-point value.

The following code makes write_map crash:

import numpy
import healpy
import qubic.io

INPUT_FILENAME = '/tmp/input.fits'
OUTPUT_FILENAME = '/tmp/output.fits'

healpy.write_map(INPUT_FILENAME, numpy.arange(12))
pixels = qubic.io.read_map(INPUT_FILENAME)
qubic.io.write_map(OUTPUT_FILENAME, pixels) # bang

The error is the following:

Traceback (most recent call last):
  File "error.py", line 10, in <module>
    qubic.io.write_map(OUTPUT_FILENAME, pixels) # bang
  File "/home/tomasi/work/qubic/qubic/qubic/io/_io.py", line 177, in write_map
    coord = map.header['coordsys'].upper()
TypeError: list indices must be integers, not str

The problem lies in the fact that when qubic.io.read_map uses Healpy to read a map, it stores the header (in pixels.header) as a list instead of a astropy.io.header.Header object. I'll shortly submit a PR to fix this small issue.

Healpy used to store map as float32 by default, but this behaviour was changed in 1.15.0 : it now use the original data type. Qubicsoft still has the old healpy behaviour and we should also move to the new one.

Conda on MacOS Ventura installs healpy with a version 0.0.0, which is rejected by the dependency specification.