Example #1
0
def median_bounds(im, peak, shared=True):

    """
    @Summary: Calculates the median of the left and right bounds found
        for each apexing peak mass

    @param im: The originating IntensityMatrix object
    @type im: pyms.GCMS.Class.IntensityMatrix
    @param peak: The Peak object
    @type peak: pyms.Peak.Class.Peak
    @param shared: Include shared ions shared with neighbouring peak
    @type shared: BooleanType

    @return: median left and right boundary offset in points
    @rtype: TupleType

    @author: Andrew Isaac
    """

    mat = im.get_matrix_list()
    ms = peak.get_mass_spectrum()
    rt = peak.get_rt()
    apex = im.get_index_at_time(rt)
    # check if RT based index is simmilar to stored index
    tmp = peak.get_pt_bounds()
    if is_list(tmp) and apex-1 < tmp[1] and tmp[1] < apex+1:
        apex = tmp[1]

    # get peak masses with non-zero intensity
    mass_ii = [ ii for ii in xrange(len(ms.mass_list)) \
        if ms.mass_spec[ii] > 0 ]

    # get stats on boundaries
    left_list = []
    right_list = []
    for ii in mass_ii:
        # get ion chromatogram as list
        ia = [ mat[scan][ii] for scan in xrange(len(mat)) ]
        area, left, right, l_share, r_share = ion_area(ia, apex)
        if shared or not l_share:
            left_list.append(left)
        if shared or not r_share:
            right_list.append(right)

    # return medians
    # NB if shared=True, lists maybe empty
    l_med = 0
    r_med = 0
    if len(left_list) > 0:
        l_med = median(left_list)
    if len(right_list) > 0:
        r_med = median(right_list)

    return l_med, r_med
Example #2
0
def median_bounds(im, peak, shared=True):
    """
    @Summary: Calculates the median of the left and right bounds found
        for each apexing peak mass

    @param im: The originating IntensityMatrix object
    @type im: pyms.GCMS.Class.IntensityMatrix
    @param peak: The Peak object
    @type peak: pyms.Peak.Class.Peak
    @param shared: Include shared ions shared with neighbouring peak
    @type shared: BooleanType

    @return: median left and right boundary offset in points
    @rtype: TupleType

    @author: Andrew Isaac
    """

    mat = im.get_matrix_list()
    ms = peak.get_mass_spectrum()
    rt = peak.get_rt()
    apex = im.get_index_at_time(rt)
    # check if RT based index is simmilar to stored index
    tmp = peak.get_pt_bounds()
    if is_list(tmp) and apex - 1 < tmp[1] and tmp[1] < apex + 1:
        apex = tmp[1]

    # get peak masses with non-zero intensity
    mass_ii = [ ii for ii in xrange(len(ms.mass_list)) \
        if ms.mass_spec[ii] > 0 ]

    # get stats on boundaries
    left_list = []
    right_list = []
    for ii in mass_ii:
        # get ion chromatogram as list
        ia = [mat[scan][ii] for scan in xrange(len(mat))]
        area, left, right, l_share, r_share = ion_area(ia, apex)
        if shared or not l_share:
            left_list.append(left)
        if shared or not r_share:
            right_list.append(right)

    # return medians
    # NB if shared=True, lists maybe empty
    l_med = 0
    r_med = 0
    if len(left_list) > 0:
        l_med = median(left_list)
    if len(right_list) > 0:
        r_med = median(right_list)

    return l_med, r_med
Example #3
0
    def info(self, print_scan_n=False):

        """
        @summary: Prints some information about the data

        @param print_scan_n: If set to True will print the number
            of m/z values in each scan
        @type print_scan_n: BooleanType

        @author: Vladimir Likic
        """

        # print the summary of simply attributes
        print " Data retention time range: %.3f min -- %.3f min" % \
                (self.__min_rt/60.0, self.__max_rt/60)
        print " Time step: %.3f s (std=%.3f s)" % ( self.__time_step, \
                self.__time_step_std )
        print " Number of scans: %d" % ( len(self.__scan_list) )
        print " Minimum m/z measured: %.3f" % ( self.__min_mass )
        print " Maximum m/z measured: %.3f" % ( self.__max_mass )

        # calculate median number of m/z values measured per scan
        n_list = []
        for ii in range(len(self.__scan_list)):
            scan = self.__scan_list[ii]
            n = len(scan)
            n_list.append(n)
            if print_scan_n: print n
        mz_mean = mean(n_list)
        mz_median = median(n_list)
        print " Mean number of m/z values per scan: %d" % ( mz_mean )
        print " Median number of m/z values per scan: %d" % ( mz_median )
Example #4
0
def __median_window(ia, wing_length):

    """
    @summary: Applies median-window averaging on the array of intensities.

    @param ia: Intensity array
    @type ia: nympy.core.ndarray
    @param wing_length: An integer value representing the number of
        points on either side of a point in the ion chromatogram
    @type wing_length: IntType

    @return: Smoothed intensity array
    @rtype: nympy.core.ndarray

    @author: Vladimir Likic
    """

#print " -> Window smoothing (median): the wing is %d point(s)" % (wing_length)

    ia_denoise = numpy.repeat([0], ia.size)

    index = 0
    end = ia.size - 1

    while index <= end:
        left = index - wing_length
        right = index + wing_length + 1
        if left < 0: left = 0
        slice = ia[left:right]
        ia_denoise[index] = median(slice)
        index = index + 1

    return ia_denoise
Example #5
0
    def info(self, print_scan_n=False):

        """
        @summary: Prints some information about the data

        @param print_scan_n: If set to True will print the number
            of m/z values in each scan
        @type print_scan_n: BooleanType

        @author: Vladimir Likic
        """

        # print the summary of simply attributes
        print " Data retention time range: %.3f min -- %.3f min" % \
                (self.__min_rt/60.0, self.__max_rt/60)
        print " Time step: %.3f s (std=%.3f s)" % ( self.__time_step, \
                self.__time_step_std )
        print " Number of scans: %d" % ( len(self.__scan_list) )
        print " Minimum m/z measured: %.3f" % ( self.__min_mass )
        print " Maximum m/z measured: %.3f" % ( self.__max_mass )

        # calculate median number of m/z values measured per scan
        n_list = []
        for ii in range(len(self.__scan_list)):
            scan = self.__scan_list[ii]
            n = len(scan)
            n_list.append(n)
            if print_scan_n: print n
        mz_mean = mean(n_list)
        mz_median = median(n_list)
        print " Mean number of m/z values per scan: %d" % ( mz_mean )
        print " Median number of m/z values per scan: %d" % ( mz_median )
Example #6
0
def __median_window(ia, wing_length):
    """
    @summary: Applies median-window averaging on the array of intensities.

    @param ia: Intensity array
    @type ia: nympy.core.ndarray
    @param wing_length: An integer value representing the number of
        points on either side of a point in the ion chromatogram
    @type wing_length: IntType

    @return: Smoothed intensity array
    @rtype: nympy.core.ndarray

    @author: Vladimir Likic
    """

    #print " -> Window smoothing (median): the wing is %d point(s)" % (wing_length)

    ia_denoise = numpy.repeat([0], ia.size)

    index = 0
    end = ia.size - 1

    while index <= end:
        left = index - wing_length
        right = index + wing_length + 1
        if left < 0: left = 0
        slice = ia[left:right]
        ia_denoise[index] = median(slice)
        index = index + 1

    return ia_denoise