def add_gaussv_noise_ic(ic: IonChromatogram, scale: int, cutoff: int,
prop: float):
"""
Adds noise to an ic. The noise value is drawn from a normal
distribution, the scale of this distribution depends on the
value of the ic at the point where the noise is being added
:param ic: The IonChromatogram
:type ic: pyms.IonChromatogram.IonChromatogram
:param cutoff: The level below which the intensity of the ic at that point
has no effect on the scale of the noise distribution
:type cutoff: int
:param scale: The scale of the normal distribution for ic values below the cutoff
is modified for values above the cutoff
:type scale: int
:param prop: For ic values above the cutoff, the scale is multiplied by the ic
value multiplied by prop
:type prop: float
:author: Sean O'Callaghan
"""
noise = numpy.zeros(len(ic))
i_array = ic.get_intensity_array()
# time_list = ic.get_time_list()
for i in range(len(ic)):
if i_array[i] < cutoff:
noise[i] = numpy.random.normal(0.0, scale, 1)
else:
noise[i] = numpy.random.normal(0.0, scale * i_array[i] * prop, 1)
i_array_with_noise = noise + i_array
ic.set_intensity_array(i_array_with_noise)
def add_gaussc_noise_ic(ic: IonChromatogram, scale: float):
"""
Adds noise drawn from a normal distribution with constant scale to an ion chromatogram
:param ic: The ion Chromatogram
:type ic: pyms.IonChromatogram.IonChromatogram
:param scale: The scale of the normal distribution
:type scale: float
:author: Sean O'Callaghan
"""
noise = numpy.random.normal(0.0, scale, (len(ic)))
i_array_with_noise = ic.get_intensity_array() + noise
ic.set_intensity_array(i_array_with_noise)