Python numpy.poly1d函数代码示例

	def calFinished(self,items):
		ADC,DAC,correct = items
		CHAN = self.I.DAC.CHANS[DAC]
		X= np.linspace(CHAN.range[0],CHAN.range[1],4096)
		
		fitvals = np.polyfit(X,correct,3)
		fitfn = np.poly1d(fitvals)
		DIFF = (fitfn(X)-correct)
		intercept = DIFF.min()
		slope = (DIFF.max()-DIFF.min())/255.
		OFF = np.int16((( DIFF-intercept)/slope)) # compress the errors into an unsigned BYTE each
		print (min(OFF),max(OFF),len(OFF))

		self.p1.setData(X,correct-X)
		self.DACPLOT.enableAutoRange(axis = self.DACPLOT.plotItem.vb.YAxis)
		reply = QtGui.QMessageBox.question(self, 'Cross Check','Does the plot look okay? proceed with writing to flash?', QtGui.QMessageBox.Yes, QtGui.QMessageBox.No)
		if reply == QtGui.QMessageBox.No:
			return False
		
		self.DAC_CALS[DAC]=struct.pack('6f',slope,intercept,fitvals[0],fitvals[1],fitvals[2],fitvals[3])
		self.DAC_RELOADS[DAC] = OFF
		print( '\n','>'*20,DAC,'<'*20)
		print('Offsets :',OFF[:20],'...')
		fitfn = np.poly1d(fitvals)
		YDATA = fitfn(X) - (OFF*slope+intercept)
		LOOKBEHIND = 100;LOOKAHEAD=100                      
		OFF=np.array([np.argmin(np.fabs(YDATA[max(B-LOOKBEHIND,0):min(4095,B+LOOKAHEAD)]-X[B]) )- (B-max(B-LOOKBEHIND,0)) for B in range(0,4096)])
		CHAN.load_calibration_table(OFF)
		self.tabs.setEnabled(True)

		self.__PVCH__(DAC,ADC,self.curdacrow,[CHAN.CodeToV(100),CHAN.CodeToV(4000),200]) #Check if fixed

 def test_polydiv(self):
     b = np.poly1d([2, 6, 6, 1])
     a = np.poly1d([-1j, (1+2j), -(2+1j), 1])
     q, r = np.polydiv(b, a)
     assert_equal(q.coeffs.dtype, np.complex128)
     assert_equal(r.coeffs.dtype, np.complex128)
     assert_equal(q*a + r, b)

def var_fit(var_mean,var_name):
	size_list = []
	throuput_list = []
	for var in var_mean:
		get_per,set_per = normal_ops
		get_per_s = "%.2f" % get_per
		set_per_s = "%.2f" % set_per
		if (var_name=='key'):
			upperlimit = 64
			filename = 'data_collected/'+str(var)+'_'+str(normal_value)+'_'+str(normal_hash)+'_'+get_per_s+'_'+set_per_s+'.out'
		elif (var_name=='value'):
			upperlimit = 2048
			filename = 'data_collected/'+str(normal_key)+'_'+str(var)+'_'+str(normal_hash)+'_'+get_per_s+'_'+set_per_s+'.out'
		with open(filename,'r') as f:
			load, time = zip(*[(int(line.strip().split(',')[0]), float(line.strip().split(',')[1])) for line in f])			
			z = np.polyfit(time,load,2)
			p = np.poly1d(z)
			size = var
			throuput = p(1)
			size_list.append(size)
			throuput_list.append(throuput)
	#Record raw data point
	with open ('data_collected/'+var_name+'_throuput','w') as g:
		for size,throuput in zip(size_list,throuput_list):
			g.write(str(size)+','+str(throuput)+'\n')	

	#Recide fit data point
	z = np.polyfit(np.array(size_list),np.array(throuput_list),1)
	p = np.poly1d(z)
	size_fit_list = [i for i in range(1,upperlimit)]
	throuput_fit_list = [p(i) for i in size_fit_list]
	with open ('data_collected/'+var_name+'_throuput_fit','w') as g:
		for size,throuput in zip(np.array(size_fit_list),np.array(throuput_fit_list)):
			g.write(str(size)+','+str(throuput)+'\n')
	var_plot(var_name,list(z))

def extractfeatures(buf):
    global yp1, yp2, yp3, x
    x = range(len(buf))
    features = []
    link1 = []
    link2 = []
    link3 = []
    for p in buf:
        link1.append(p[0])
        link2.append(p[1])
        link3.append(p[2])
    features.append(avgdelta(link1))
    features.append(avgdelta(link2))
    features.append(avgdelta(link3))
    features.append(abs(link1[0]-link1[len(link1)-1]))
    features.append(abs(link2[0]-link2[len(link2)-1]))
    features.append(abs(link3[0]-link3[len(link3)-1]))
    z1 = np.polyfit(x,link1,2)
    z2 = np.polyfit(x,link2,2)
    z3 = np.polyfit(x,link3,2)
    abslink1 = [abs(z1[i]) for i in range(len(z1)-1)]
    abslink2 = [abs(z2[i]) for i in range(len(z2)-1)]
    abslink3 = [abs(z3[i]) for i in range(len(z3)-1)]
    for a in abslink1:
        features.append(a)
    for a in abslink2:
        features.append(a)
    for a in abslink3:
        features.append(a)
    yp1 = np.poly1d(z1)
    yp2 = np.poly1d(z2)
    yp3 = np.poly1d(z3)
    return features

	def plot(self):
		self.worksheet()
		fig, ax = plt.subplots()
		axes = [ax, ax.twinx(), ax.twinx()]
		fig.subplots_adjust(right=0.75)
		axes[-1].spines['right'].set_position(('axes', 1.2))
		colors = ('Green', 'Red', 'Blue')
		cur=np.poly1d(np.polyfit(self.DISCHARGE,self.current,2))
		eff=np.poly1d(np.polyfit(self.DISCHARGE,self.EFFICIENCY,2))
		head=np.poly1d(np.polyfit(self.DISCHARGE,self.del_head,2))
		dis=np.linspace(self.DISCHARGE[0],self.DISCHARGE[9],500)
		#Head Axis Plotting
		axes[2].plot(dis,eff(dis), color=colors[0])
		axes[2].plot(self.DISCHARGE,self.EFFICIENCY,'ko',color=colors[0])
		axes[2].set_ylabel('Efficiency (%)', color=colors[0])
		axes[2].tick_params(axis='y', colors=colors[0])
		#Current Axis Plotting
		axes[1].plot(dis,cur(dis), color=colors[1])
		axes[1].plot(self.DISCHARGE,self.current,'k+',color=colors[1])
		axes[1].set_ylabel('Current (A)', color=colors[1])
		axes[1].tick_params(axis='y', colors=colors[1])
		#Efficiency Axis Plotting
		axes[0].plot(dis,head(dis), color=colors[2])
		axes[0].plot(self.DISCHARGE,self.del_head,'kx',color=colors[2])
		axes[0].set_ylabel('Head (m)', color=colors[2])
		axes[0].tick_params(axis='y', colors=colors[2])
		axes[0].set_xlabel('Discharge in lps')
		plt.grid()
		plt.show()
		self.DISCHARGE = []
		self.EFFICIENCY= []

def daub(p):
    """
    The coefficients for the FIR low-pass filter producing Daubechies wavelets.

    p>=1 gives the order of the zero at f=1/2.
    There are 2p filter coefficients.

    Parameters
    ----------
    p : int
        Order of the zero at f=1/2, can have values from 1 to 34.

    """
    sqrt = np.sqrt
    if p < 1:
        raise ValueError("p must be at least 1.")
    if p==1:
        c = 1/sqrt(2)
        return np.array([c,c])
    elif p==2:
        f = sqrt(2)/8
        c = sqrt(3)
        return f*np.array([1+c,3+c,3-c,1-c])
    elif p==3:
        tmp  = 12*sqrt(10)
        z1 = 1.5 + sqrt(15+tmp)/6 - 1j*(sqrt(15)+sqrt(tmp-15))/6
        z1c = np.conj(z1)
        f = sqrt(2)/8
        d0 = np.real((1-z1)*(1-z1c))
        a0 = np.real(z1*z1c)
        a1 = 2*np.real(z1)
        return f/d0*np.array([a0, 3*a0-a1, 3*a0-3*a1+1, a0-3*a1+3, 3-a1, 1])
    elif p<35:
        # construct polynomial and factor it
        if p<35:
            P = [comb(p-1+k,k,exact=1) for k in range(p)][::-1]
            yj = np.roots(P)
        else:  # try different polynomial --- needs work
            P = [comb(p-1+k,k,exact=1)/4.0**k for k in range(p)][::-1]
            yj = np.roots(P) / 4
        # for each root, compute two z roots, select the one with |z|>1
        # Build up final polynomial
        c = np.poly1d([1,1])**p
        q = np.poly1d([1])
        for k in range(p-1):
            yval = yj[k]
            part = 2*sqrt(yval*(yval-1))
            const = 1-2*yval
            z1 = const + part
            if (abs(z1)) < 1:
                z1 = const - part
            q = q * [1,-z1]

        q = c * np.real(q)
        # Normalize result
        q = q / np.sum(q) * sqrt(2)
        return q.c[::-1]
    else:
        raise ValueError("Polynomial factorization does not work "
              "well for p too large.")

def fit(data, nz):
    x = [0 for iz in range(0, nz, 1)]
    y = [0 for iz in range(0, nz, 1)]
    z = [iz for iz in range(0, nz, 1)]

    for iz in range(0, nz, 1):
        x[iz], y[iz] = ndimage.measurements.center_of_mass(np.array(data[:,:,iz]))

    #Fit centerline in the Z-X plane using polynomial function
    print '\nFit centerline in the Z-X plane using polynomial function...'
    coeffsx = np.polyfit(z, x, 1)
    polyx = np.poly1d(coeffsx)
    x_fit = np.polyval(polyx, z)
    print 'x_fit'
    print x_fit

    #Fit centerline in the Z-Y plane using polynomial function
    print '\nFit centerline in the Z-Y plane using polynomial function...'
    coeffsy = np.polyfit(z, y, 1)
    polyy = np.poly1d(coeffsy)
    y_fit = np.polyval(polyy, z)


    #### 3D plot
    fig1 = plt.figure()
    ax = Axes3D(fig1)
    ax.plot(x,y,z,zdir='z')
    ax.plot(x_fit,y_fit,z,zdir='z')
    plt.show()
    return x, y, x_fit, y_fit

def Q(dim, dfd=np.inf):
    """ Q polynomial

    If dfd == inf (the default), then
    Q(dim) is the (dim-1)-st Hermite polynomial 

    H_j(x) = (-1)^j * e^{x^2/2} * (d^j/dx^j e^{-x^2/2})

    If dfd != inf, then it is the polynomial Q defined in

    Worsley, K.J. (1994). 'Local maxima and the expected Euler
    characteristic of excursion sets of \chi^2, F and t fields.'
    Advances in Applied Probability, 26:13-42.
    """
    m = dfd
    j = dim
    if j > 0:
        poly = hermitenorm(j - 1)
        poly = np.poly1d(np.around(poly.c))
        if np.isfinite(m):
            for l in range((j - 1) / 2 + 1):
                f = np.exp(
                    gammaln((m + 1) / 2.0)
                    - gammaln((m + 2 - j + 2 * l) / 2.0)
                    - 0.5 * (j - 1 - 2 * l) * (np.log(m / 2.0))
                )
                poly.c[2 * l] *= f
        return np.poly1d(poly.c)
    else:
        raise ValueError, "Q defined only for dim > 0"

def StepFit(df_timeser):
  # receives the temporal series as a dataframe with 3 columns: time, nflux, Q
  # NaN must be already droped
  # df must be already sorted by time
  
  # An array of quarters, non duplicate items.
  nondup = np.unique(df_timeser['Q'].values)
  
  # Go through time series, quarter by quarter
  if len(nondup) > 1:
    # Save the first quarter of the LC
    df_Fit = df_timeser[ df_timeser.Q == nondup[0] ]
      
    # Iterate up to the n-1 element
    for index,q_item in enumerate( nondup[:len(nondup)-1] ): # indexing is OK!!!
      df_tmp1 = df_timeser[ df_timeser.Q == q_item ]
      df_tmp2 = df_timeser[ df_timeser.Q == nondup[index+1] ]
      # fit the 2 linear fits using: np.polyfit, np.polyval, p = np.poly1d(z)
      p1 = np.poly1d( np.polyfit(df_tmp1['time'].values, df_tmp1['nflux'].values,1) )
      p2 = np.poly1d( np.polyfit(df_tmp2['time'].values, df_tmp2['nflux'].values,1) )
      # then evaluate the borders of each piece, in the corresponding fit
      # and determine the offset.
      Offset = p1(df_tmp1['time'].values[-1]) -  p2(df_tmp2['time'].values[-1])
      # now add the offset to the second piece
      df_tmp2['nflux'] += Offset
      # and concatenate the 2nd piece with the previous
      df_Fit = concat( [df_Fit, df_tmp2] )
  else:
    df_Fit = df_timeser
    print 'no fit made, only ONE quarter in LC'
  #return out of ELSE statement
  return df_Fit

    def debye_T(self, x):
        
        self.__EoB = []
        self.__GoB = []
        self.__B = []
        self.__V = []
        
        dic = self.get_Cij()
        for scale in sorted(dic.keys()):
            (a, b, c) = self.calculate_moduli(scale)
            self.__EoB.append(c)
            self.__GoB.append(b)
            self.__B.append(a)
            self.__V.append(float(scale)**3./2.)
        
        
        c1= np.polyfit(self.__V, self.__EoB, 4)
        p_EoB = np.poly1d(c1)
           
        c2= np.polyfit(self.__V, self.__GoB, 4)
        p_GoB = np.poly1d(c2)
        
        c3= np.polyfit(self.__V, self.__B, 4)
        p_B = np.poly1d(c3)

        Const = 1.
        theta = Const * ( 1./3.*(p_EoB(x))**(-3./2.) + 2./3.*(p_GoB(x))**(-3./2.) )
        return theta

def polynomial_fitting(input_array, degree=4, verbose=False, skip_col=[], skip_row=[]):
    array_org = input_array.copy()
    shape = input_array.shape

    # apply on rows
    for row in range(shape[0]):
        if row in skip_row:
            pass
        else:
            poly = np.poly1d(np.polyfit(x=np.linspace(1, shape[1], shape[1]), y=input_array[row,:], deg=degree))
            input_array[row,:] = poly(np.linspace(1, shape[1], shape[1]))

    # apply on columns
    for col in range(shape[1]):
        if col in skip_col:
            pass
        else:
            poly = np.poly1d(np.polyfit(x=np.linspace(1, shape[0], shape[0]), y=input_array[:,col], deg=degree))
            input_array[:,col] = poly(np.linspace(1, shape[0], shape[0]))

    if verbose:
        print("Polynomial fitting")
        print("Degree of the fitting polynomial : {}".format(degree))
        print("-----Normalized Table-------")
        print(input_array)
        print("-----Original Table-------")
        print(array_org)
        print("")
    return input_array

def bch_18_6(symbol_version):
    """Calculate BCH(18,6) on symbol version number.

    This function is not used as in the specs we have a reference table
    covering all the symbol version. It was just to test if I would have
    obtained the same results.
    """
    data_bit_string = to_binstring(symbol_version, 6)
    numerator = (
            poly1d([int(x) for x in data_bit_string]) *
            poly1d([1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]))
    generator_polynomial = poly1d([1, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1])
    _quotient, remainder = numerator / generator_polynomial
    coeff_list = [abs(int(x)) for x in remainder.coeffs]
    # don't know why i have some 2 and 3 coefficients. used a modulo operation
    # to obtain the expected results
    coeff_list = [x % 2 for x in coeff_list]
    while len(coeff_list) < 12:
        coeff_list.insert(0, 0)
    coeff_string = ''
    for coeff in coeff_list:
        coeff_string += str(coeff)

    result = data_bit_string + coeff_string
    return result

def drawStats2(prices, period):
	ps2 = [p['close'] for p in prices][-140:-115]
	ps = [p['close'] for p in prices][-140:-120]
	phs = [p['high'] for p in prices][-140:-120]
	pls = [p['low'] for p in prices][-140:-120]
	
	l = len(prices)
	ts = np.arange(20)
	pz = np.poly1d(np.polyfit(ts, ps, 1))
	phz = np.poly1d(np.polyfit(ts, phs, 1))
	plz = np.poly1d(np.polyfit(ts, pls, 1))
	
	fig = plt.figure()
	ax1 = fig.add_subplot(311)
	ax1.plot(ts, ps, '-', ts, pz(ts), '-', ts, phz(ts), '--', ts, plz(ts), '--')
	#plt.plot(ts, ps, 'o', label='Original data', linestyle='-', markersize=2)
	#plt.plot(ts, m * ts + c, 'r', label='Fitted line')
	#plt.legend()
	ax2 = fig.add_subplot(312)
	ax2.plot(ts, (pz(ts) - plz(ts)) - (phz(ts) - pz(ts)), '-')
	ax2.grid()
	ts2 = np.arange(len(ps2))
	ax3 = fig.add_subplot(313)
	ax3.plot(ts2, ps2, '-')
	multi = MultiCursor(fig.canvas, (ax1, ax2), color='r', lw=1, horizOn=False, vertOn=True)
	plt.show()
	return

def optimum_polyfit(x, y, score=functoolz.compose(np.max, np.abs), max_degree=50, stop_at=1e-10):
    """
    Optimize the degree of a polyfit polynomial so that score(y - poly(x)) is minimized.

    :param max_degree: The maximum degree to try. LinAlgErrors are automatically ignored.
    :param stop_at: If a score lower than this is reached, the function returns early
    :param score: The score function that is applied to y - poly(x). Default: max deviation.
    :return A tuple (poly1d object, degree, score)
    """
    scores = np.empty(max_degree - 1, dtype=np.float64)
    # Ignore rank warnings now, but do not ignore for the final polynomial if not early returning
    with warnings.catch_warnings():
        warnings.simplefilter('ignore', np.RankWarning)
        for deg in range(1, max_degree):
            # Set score to max float value
            try:
                poly = np.poly1d(np.polyfit(x, y, deg))
            except np.linalg.LinAlgError:
                scores[deg - 1] = np.finfo(np.float64).max
                continue
            scores[deg - 1] = score(y - poly(x))
            # Early return if we found a polynomial that is good enough
            if scores[deg - 1] <= stop_at:
                return poly, deg, scores[deg - 1]
    # Find minimum score
    deg = np.argmin(scores) + 1
    # Compute polyfit for that degreet
    poly = np.poly1d(np.polyfit(x, y, deg))
    return poly, deg, np.min(scores)

def smooth_regress(path, dt, order):
    """
    path: data frame with at least columns 't', 'lat', 'lon'
    dt: resampling time interval
    order: order of the polynomial to use
    return: interpolated path
    """
    import pandas as pd
    import numpy as np
    from numpy import polyfit, poly1d

    start = path.t.iloc[0]
    end = path.t.iloc[-1]
    # new ts sequence
    nt = start + np.linspace(0, end - start, (end - start) / dt + 1)

    avg_t = np.mean(path['t'])
    avg_lat = np.mean(path['lat'])
    avg_lon = np.mean(path['lon'])

    lat = np.poly1d(np.polyfit(path['t'] - avg_t, path['lat'] - avg_lat, order))
    lon = np.poly1d(np.polyfit(path['t'] - avg_t, path['lon'] - avg_lon, order))

    r = pd.DataFrame(columns = ('t', 'lat', 'lon'))
    r['t'] = nt
    r['lat'] = list(map(lat, nt - avg_t))
    r['lon'] = list(map(lon, nt - avg_t))

    # Repair path
    r['lat'] += avg_lat
    r['lon'] += avg_lon
    r.set_index('t', inplace=True)

    return r