def add_gaussv_noise(im: IntensityMatrix, scale: float, cutoff: int,
prop: float):
"""
adds noise to an IntensityMatrix object
:param im: the intensity matrix object
:type im: pyms.IntensityMatrix.IntensityMatrix
:param scale: the scale of the normal distribution from which the noise is drawn
:type scale: float
: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
:type scale: int
:param prop: For intensity values above the cutoff, the scale is
multiplied by the ic value multiplied by prop
:type prop: float
:author: Sean O'Callaghan
"""
n_scan, n_mz = im.size
for i in range(n_mz):
ic = im.get_ic_at_index(i)
add_gaussv_noise_ic(ic, scale, cutoff, prop)
im.set_ic_at_index(i, ic)
def peak_top_ion_areas(
im: IntensityMatrix,
peak: Peak,
n_top_ions: int = 5,
max_bound: int = 0,
) -> Dict[float, float]:
"""
Calculate and return the ion areas of the five most abundant ions in the peak.
:param im: The originating IntensityMatrix object.
:param peak:
:param n_top_ions: Number of top ions to return areas for.
:param max_bound: Optional value to limit size of detected bound.
:return: Dictionary of ``ion : ion_area pairs``.
:authors: Sean O'Callaghan, Dominic Davis-Foster (type assertions)
"""
if not isinstance(im, IntensityMatrix):
raise TypeError("'im' must be an IntensityMatrix object")
if not isinstance(peak, Peak):
raise TypeError("'peak' must be a Peak object")
if not isinstance(n_top_ions, int):
raise TypeError("'n_top_ions' must be an integer")
if not isinstance(max_bound, int):
raise TypeError("'max_bound' must be an integer")
# ms = peak.mass_spectrum
rt = peak.rt
apex = im.get_index_at_time(rt)
ion_areas = {} # Dictionary to store ion:ion_area pairs
top_ions = peak.top_ions(n_top_ions)
# print(top_ions)
for ion in top_ions:
ion_chrom = im.get_ic_at_mass(ion)
# need ia as a list not numpy array so use .tolist()
ia = ion_chrom.intensity_array.tolist()
area, left, right, l_share, r_share = ion_area(ia, apex, max_bound)
# need actual mass for single ion areas
ion_areas[ion] = area
return ion_areas
def test_equality(self, im):
assert im == IntensityMatrix(im.time_list, im.mass_list,
im.intensity_array)
assert im != test_string
assert im != test_int
assert im != test_float
assert im != test_tuple
assert im != test_list_ints
assert im != test_list_strs
def add_gaussc_noise(im: IntensityMatrix, scale: float):
"""
Adds noise to an IntensityMatrix object
:param im: the intensity matrix object
:type im: pyms.IntensityMatrix.IntensityMatrix
:param scale: the scale of the normal distribution from which the noise is drawn
:type scale: float
:author: Sean O'Callaghan
"""
n_scan, n_mz = im.size
for i in range(n_mz):
ic = im.get_ic_at_index(i)
add_gaussc_noise_ic(ic, scale)
im.set_ic_at_index(i, ic)
def gcms_sim(
time_list: List[float],
mass_list: List[float],
peak_list: List[Peak.Peak],
) -> IntensityMatrix:
"""
Simulator of GCMS data.
:param time_list: the list of scan times
:param mass_list: the list of m/z channels
:param peak_list: A list of peaks
:return: A simulated Intensity Matrix object
:author: Sean O'Callaghan
"""
n_mz = len(mass_list)
n_scan = len(time_list)
t1 = time_list[0]
period = time_list[1] - t1
# initialise a 2D numpy array for intensity matrix
i_array = numpy.zeros((n_scan, n_mz), 'd')
for peak in peak_list:
print('-', end='')
index = int((peak.rt - t1) / period)
height = sum(peak.mass_spectrum.mass_spec)
# standard deviation = area/(height * sqrt(2/pi))
sigma: float = peak.area / (height *
(math.sqrt(2 * math.pi))) # type: ignore
print("width", sigma)
for i in range(len(peak.mass_spectrum.mass_list)):
ion_height = peak.mass_spectrum.mass_spec[i]
ic = chromatogram(n_scan, index, sigma, ion_height)
i_array[:, i] += ic
im = IntensityMatrix(time_list, mass_list, i_array)
return im
def gcms_sim(time_list: List, mass_list: List,
peak_list: Peak) -> IntensityMatrix:
"""
Simulator of GCMS data
:param time_list: the list of scan times
:type time_list: list
:param mass_list: the list of m/z channels
:type mass_list: list
:param peak_list: A list of peaks
:type peak_list: :class:`list` of :class:`pyms.Peak.Class.Peak` objects
:return: A simulated Intensity Matrix object
:rtype: pyms.IntensityMatrix.IntensityMatrix
:author: Sean O'Callaghan
"""
n_mz = len(mass_list)
n_scan = len(time_list)
t1 = time_list[0]
period = time_list[1] - t1
# initialise a 2D numpy array for intensity matrix
i_array = numpy.zeros((n_scan, n_mz), 'd')
for peak in peak_list:
print("-", end='')
index = int((peak.rt - t1) / period)
height = sum(peak.get_mass_spectrum().mass_spec)
# standard deviation = area/(height * sqrt(2/pi))
sigma = peak.area / (height * (math.sqrt(2 * math.pi)))
print("width", sigma)
for i in range(len(peak.get_mass_spectrum().mass_list)):
ion_height = peak.get_mass_spectrum().mass_spec[i]
ic = chromatogram(n_scan, index, sigma, ion_height)
i_array[:, i] += ic
im = IntensityMatrix(time_list, mass_list, i_array)
return im
def test_intensity_array_errors(self, obj, im, expects):
with pytest.raises(expects):
IntensityMatrix(im.time_list, im.mass_list, obj)
def test_mass_list_errors(self, obj, im, expects):
with pytest.raises(TypeError):
IntensityMatrix(im.time_list, obj, im.intensity_array)
def test_creation(self, im):
assert isinstance(im, IntensityMatrix)
IntensityMatrix(im.time_list, im.mass_list, im.intensity_array)
