Python pylab.amax函数代码示例

def classifier_normalize(image,size=32):
    """Normalize characters for classification."""
    if amax(image)<1e-3: return zeros((size,size))
    cimage = array(image*1.0/amax(image),'f')
    cimage = isotropic_rescale(cimage,size)
    cimage = csnormalize(cimage)
    return cimage

def test1():
    vector_full = NP.array([1.0, 2.5, 2.8, 4.1, 5.1, 5.9, 6.9, 8.1])
    vector = vector_full[:-2]
    t =  NP.arange(vector.shape[0])
    showArray('t', t) 
    showArray('vector', vector)    
    
    mask = [True] * vector.shape[0]
    mask[2] = False
    print 'mask', len(mask), mask
   
    masked_vector = applyMask1D(vector, mask)
    masked_t = applyMask1D(vector, mask)
    trend = getTrend(t, vector)
    print trend
    for i in range(masked_t.shape[0]):
        v_pred = trend[0] + masked_t[i] * trend[1]
        print i, masked_vector[i], v_pred, v_pred - masked_vector[i]
    
    predicted = NP.array([trend[0] + i * trend[1] for i in range(masked_vector.shape[0])])
    corrected = NP.array([masked_vector[i] - predicted[i] for i in range(masked_vector.shape[0])])
    masked_s = NP.transpose(NP.vstack([masked_vector, predicted, corrected]))
    
    showArray('masked_t', masked_t) 
    showArray('masked_s', masked_s)    
    # the main axes is subplot(111) by default
    PL.plot(masked_t, masked_s)
    s_range = PL.amax(masked_s) - PL.amin(masked_s)
    axis([PL.amin(masked_t), PL.amax(masked_t), PL.amin(masked_s) - s_range*0.1, PL.amax(masked_s) + s_range*0.1 ])
    xlabel('time (days)')
    ylabel('downloads')
    title('Dowloads over time')
    show()

def csnormalize(image,f=0.75):
    """Center and size-normalize an image."""
    bimage = 1*(image>mean([amax(image),amin(image)]))
    w,h = bimage.shape
    [xs,ys] = mgrid[0:w,0:h]
    s = sum(bimage)
    if s<1e-4: return image
    s = 1.0/s
    cx = sum(xs*bimage)*s
    cy = sum(ys*bimage)*s
    sxx = sum((xs-cx)**2*bimage)*s
    sxy = sum((xs-cx)*(ys-cy)*bimage)*s
    syy = sum((ys-cy)**2*bimage)*s
    w,v = eigh(array([[sxx,sxy],[sxy,syy]]))
    l = sqrt(amax(w))
    if l>0.01:
        scale = f*max(image.shape)/(4.0*l)
    else:
        scale = 1.0
    m = array([[1.0/scale,0],[0.0,1.0/scale]])
    w,h = image.shape
    c = array([cx,cy])
    d = c-dot(m,array([w/2,h/2]))
    image = interpolation.affine_transform(image,m,offset=d,order=1)
    return image

def fwhm_2gauss(x, y, dx=0.001):
	'''
	Finds the FWHM for the profile y(x), with accuracy dx=0.001
	Uses a 2-Gauss 1D fit.
	'''
	popt, pcov = curve_fit(gauss2, x, y);
	xx = pl.arange(pl.amin(x), pl.amax(x)+dx, dx);
	ym = gauss2(xx, popt[0], popt[1], popt[2], popt[3], popt[4], popt[5])
	hm = pl.amax(ym/2.0);
	y_diff = pl.absolute(ym-hm);
	y_diff_sorted = pl.sort(y_diff);
	i1 = pl.where(y_diff==y_diff_sorted[0]);
	i2 = pl.where(y_diff==y_diff_sorted[1]);
	fwhm = pl.absolute(xx[i1]-xx[i2]);
	return hm, fwhm, xx, ym

def plot_tuneshifts_2(ax, spectrum, scan_values, Qs=1, fitrange=None, fittype=None):

    (spectral_lines, spectral_intensity) = spectrum

    # Normalize power.
    normalized_intensity = spectral_intensity / plt.amax(spectral_intensity)

    # Prepare plot environment.
    palette    = _create_cropped_cmap()

    x_grid = plt.ones(spectral_lines.shape) * plt.array(scan_values, dtype='float64')
    for file_i in xrange(len(scan_values)):
        x, y, z = x_grid[:,file_i], spectral_lines[:,file_i], normalized_intensity[:,file_i]
        tuneshift_plot = ax[0].scatter(x, y, s=192*plt.log(1+z), c=z, cmap=palette, edgecolors='None')

    # Colorbar
    cb = plt.colorbar(tuneshift_plot, ax[1], orientation='vertical')
    cb.set_label('Power [normalised]')

    if fitrange:
        if not fittype or fittype=='full':
            x, y, z, p = fit_modes_full(spectral_lines, spectral_intensity, scan_values, fitrange)
        elif fittype=="0":
            x, y, z, p = fit_modes_0(spectral_lines, spectral_intensity, scan_values, fitrange)
        else:
            raise ValueError("Wrong argument "+fittype+"! Use \"0\" or \"full\"")

        ax[0].plot(x, y, 'o', ms=8, mfc='none', mew=2, mec='limegreen')
        ax[0].plot(scan_values, z, '-', lw=2, color='limegreen')

        ax[0].text(0.95, 0.95, '$\Delta Q \sim $ {:1.2e}'.format(p[0]*1e11*Qs[0]), fontsize=36, color='w', horizontalalignment='right', verticalalignment='top', transform=ax[0].transAxes)

    def addDataVectorAccessor(self, data_vector_accessor):
        self.__data_vectors_accessors__.append(data_vector_accessor)

        _sum = pl.sum(data_vector_accessor.signal)
        _min = pl.amin(data_vector_accessor.signal)
        _max = pl.amax(data_vector_accessor.signal)

        if self.__minimal_signal__ == None:
            self.__minimal_signal__ = _sum
            self.__minimal_data_vector_accessor__ = data_vector_accessor

            self.__min_signal__ = _min
            self.__max_signal__ = _max

        if _sum < self.__minimal_signal__:
            self.__minimal_data_vector_accessor__ = data_vector_accessor
            self.__minimal_signal__ = _sum

        if _min < self.__min_signal__:
            self.__min_signal__ = _min

        if _max > self.__max_signal__:
            self.__max_signal__ = _max

        #collects unique annotations (>0) as a set
        if not data_vector_accessor.annotation == None:
            unique_annotations = pl.unique(data_vector_accessor.annotation[
                                pl.where(data_vector_accessor.annotation > 0)])
            if len(unique_annotations) > 0:
                #union of sets
                self.__unique_annotations__ |= set(unique_annotations)

	def __init__(self, X, c):
		self.n, self.N = X.shape
		self.X = X
		self.c = c

		# Calculate max value of the 2d array
		self.max = amax(X)

def average_size(img, minimum_area=10, maximum_area=40):
    "计算页面中整个连接体的 平均的大小，可能是因为manga中的字体都差不多大"
    
    components = get_connected_components(img)
    
    
    sorted_components = sorted(components,key=area_bb)
    #sorted_components = sorted(components,key=lambda x:area_nz(x,binary))
    areas = zeros(img.shape)
    
    for component in sorted_components:
        #As the input components are sorted, we don't overwrite
        #a given area again (it will already have our max value)
        if amax(areas[component])>0: continue
        #take the sqrt of the area of the bounding box
        areas[component] = area_bb(component)**0.5
        #alternate implementation where we just use area of black pixels in cc
        #areas[component]=area_nz(component,binary)
    #we lastly take the median (middle value of sorted array) within the region of interest
    #region of interest is defaulted to those ccs between 3 and 100 pixels on a side (text sized)
    aoi = areas[(areas>minimum_area)&(areas<maximum_area)]
    if len(aoi)==0:
        return 0
    print 'np.median(aoi) = ',np.median(aoi)
    
    return np.median(aoi)

def _calculate_spectra_sussix(sx, sy, Q_x, Q_y, Q_s, n_lines):

    n_turns, n_files = sx.shape

    # Allocate memory for output.        
    oxx, axx = plt.zeros((n_lines, n_files)), plt.zeros((n_lines, n_files))
    oyy, ayy = plt.zeros((n_lines, n_files)), plt.zeros((n_lines, n_files))

    # Initialise Sussix object.
    SX = PySussix.Sussix()
    
    x, xp, y, yp = sx.real, sx.imag, sy.real, sy.imag
    for file_i in xrange(n_files):
        SX.sussix_inp(nt1=1, nt2=n_turns, idam=2, ir=0, tunex=Q_x[file_i] % 1, tuney=Q_y[file_i] % 1)
        SX.sussix(x[:,file_i], xp[:,file_i], y[:,file_i], yp[:,file_i], sx[:,file_i], sx[:,file_i])

        # Amplitude normalisation
        SX.ax /= plt.amax(SX.ax)
        SX.ay /= plt.amax(SX.ay)

        # Tunes
        SX.ox = plt.absolute(SX.ox)
        SX.oy = plt.absolute(SX.oy)
        if file_i==0:
            tunexsx = SX.ox[plt.argmax(SX.ax)]
            tuneysx = SX.oy[plt.argmax(SX.ay)]
            print "\n*** Tunes from Sussix"
            print "    tunex", tunexsx, ", tuney", tuneysx, "\n"

        # Tune normalisation
        SX.ox = (SX.ox - (Q_x[file_i] % 1)) / Q_s[file_i]
        SX.oy = (SX.oy - (Q_y[file_i] % 1)) / Q_s[file_i]
    
        # Sort
        CX = plt.rec.fromarrays([SX.ox, SX.ax], names='ox, ax')
        CX.sort(order='ax')
        CY = plt.rec.fromarrays([SX.oy, SX.ay], names='oy, ay')
        CY.sort(order='ay')
        ox, ax, oy, ay = CX.ox, CX.ax, CY.oy, CY.ay
        oxx[:,file_i], axx[:,file_i], oyy[:,file_i], ayy[:,file_i] = ox, ax, oy, ay

    spectra = {}
    spectra['horizontal'] = (oxx, axx)
    spectra['vertical']   = (oyy, ayy)
        
    return spectra

def fwhm(x, y):
	hm = pl.amax(y/2.0);
	y_diff = pl.absolute(y-hm);
	y_diff_sorted = pl.sort(y_diff);
	i1 = pl.where(y_diff==y_diff_sorted[0]);
	i2 = pl.where(y_diff==y_diff_sorted[1]);
	fwhm = pl.absolute(x[i1]-x[i2]);
	return hm, fwhm

def remove_noise(line,minsize=8):
    """Remove small pixels from an image."""
    if minsize==0: return line
    bin = (line>0.5*amax(line))
    labels,n = morph.label(bin)
    sums = measurements.sum(bin,labels,range(n+1))
    sums = sums[labels]
    good = minimum(bin,1-(sums>0)*(sums<minsize))
    return good

def findHighOD(data):
    '''Find the highest OD value to set for plots'''
    hi = 0
    for c, wDict in data.items():
        for w, curve in wDict.items():
            max = py.amax(curve)
            if max > hi:
                hi = max
    return hi

def translate_back(outputs,threshold=0.7,pos=0):
    """Translate back. Thresholds on class 0, then assigns
    the maximum class to each region."""
    # print outputs
    labels,n = measurements.label(outputs[:,0]<threshold)
    mask = tile(labels.reshape(-1,1), (1,outputs.shape[1]))
    maxima = measurements.maximum_position(outputs,mask,arange(1,amax(mask)+1))
    if pos: return maxima
    return [c for (r,c) in maxima]

def QuickHull(points):
    """Randomized divide and conquer convex hull.
    
    Args:
        points: NxD matrix of points in dimension D.
    """
    N, D = points.shape
    dim = random.randint(0, D-1)
    min_dim = p.amin(points.T, dim)
    max_dim = p.amax(points.T, dim)

def plot_risetimes(a, b, **kwargs):

    # plt.ion()
    # if kwargs is not None:
    #     for key, value in kwargs.iteritems():
    #         if key == 'file_list':
    #             file_list = value
    #         if key == 'scan_line':
    #             scan_line = value
    # varray = plt.array(get_value_from_cfg(file_list, scan_line))

    n_files = a.shape[-1]
    cmap = plt.get_cmap('jet')
    c = [cmap(i) for i in plt.linspace(0, 1, n_files)]

    fig1, (ax1, ax2) = plt.subplots(1, 2, figsize=(20, 10))
    [ax.set_color_cycle(c) for ax in (ax1, ax2)]

    r = []
    for i in xrange(n_files):
        x, y = a[:,i], b[:,i]
        # xo, yo = x, y #, get_envelope(x, y)
        xo, yo = get_envelope(x, y)
        p = plt.polyfit(xo, np.log(yo), 1)

        # Right way to fit... a la Nicolas - the fit expert!
        l = ax1.plot(x, plt.log(plt.absolute(y)))
        lcolor = l[-1].get_color()
        ax1.plot(xo, plt.log(yo), color=lcolor, marker='o', mec=None)
        ax1.plot(x, p[1] + x * p[0], color=lcolor, ls='--', lw=3)

        l = ax2.plot(x, y)
        lcolor = l[-1].get_color()
        ax2.plot(xo, yo, 'o', color=lcolor)
        xi = plt.linspace(plt.amin(x), plt.amax(x))
        yi = plt.exp(p[1] + p[0] * xi)
        ax2.plot(xi, yi, color=lcolor, ls='--', lw=3)

        print p[1], p[0], 1 / p[0]
        # plt.draw()
        # ax1.cla()
        # ax2.cla()

        r.append(1/p[0])

    ax2.set_ylim(0, 1000)
    plt.figure(2)
    plt.plot(r, lw=3, c='purple')
    # plt.gca().set_ylim(0, 10000)

    # ax3 = plt.subplot(111)
    # ax3.semilogy(x, y)
    # ax3.semilogy(xo, yo)

    return r