def plot(p2D,pens,p2De,para,params_exp,thickness,tempres):
    #print tempres
    plt.subplot(511)
    
    plt.hist(p2D[:,5], bins=20, normed=True)
    x = np.linspace(0, 5, 80)  
    if para !=None :
        plt.plot(x, maxwell.pdf(x, *para),'r',x,maxwell.cdf(x, *para), 'g')
    
    plt.subplot(512)
    plt.hist(pens, bins=20, normed=True)
    z=np.linspace(0,500,200)
    plt.xlim(0,2*thickness)  
    plt.plot(z, expon.pdf(z, *params_exp),'r')#plt.plot(z, expon.pdf(z, *params_exp),'r',z,expon.cdf(z, *params_exp), 'g')
    
    plt.subplot(513)
    plt.xlim(0,thickness+1)  
    plt.plot(p2D[:,0],p2D[:,1],'b.')
    
    plt.subplot(514)
    plt.ylim(-1*10**6,1*10**6)
    plt.xlim(0,thickness+1)
    plt.plot(p2De[:,0],p2De[:,1],'b.')
    
    
    plt.subplot(515)
    plt.plot(tempres[:,0],tempres[:,1],'r-')
    
    
    
    plt.savefig()
    plt.show()
    return
Пример #2
0
def plot(p2D, pens, p2De, para, params_exp, thickness):

    plt.subplot(411)

    plt.hist(p2D[:, 5], bins=10, normed=True)
    x = np.linspace(0, 5, 80)

    plt.plot(x, maxwell.pdf(x, *para), 'r', x, maxwell.cdf(x, *para), 'g')

    plt.subplot(412)
    plt.hist(pens, bins=20, normed=True)
    z = np.linspace(0, 500, 200)
    plt.xlim(0, 2 * thickness)
    plt.plot(
        z, expon.pdf(z, *params_exp), 'r'
    )  #plt.plot(z, expon.pdf(z, *params_exp),'r',z,expon.cdf(z, *params_exp), 'g')

    plt.subplot(413)
    plt.xlim(0, thickness + 1)
    plt.plot(p2D[:, 0], p2D[:, 1], 'b.')

    plt.subplot(414)
    plt.ylim(-1 * 10**6, 1 * 10**6)
    plt.xlim(0, thickness + 1)
    plt.plot(p2De[:, 0], p2De[:, 1], 'b.')
    plt.show()
    return
Пример #3
0
def plot(p2D, pens, p2De, para, params_exp, thickness, tempres, petest,
         electron_affinity, finame):
    #print tempres
    plt.subplot(511)
    plt.xlabel('thickness[nm]')
    plt.ylabel('P')
    plt.hist(p2D[:, 5], bins=20, normed=True)
    x = np.linspace(0, 5, 80)
    if para != None:
        plt.plot(x, maxwell.pdf(x, *para), 'r', x, maxwell.cdf(x, *para), 'g')

    plt.subplot(512)
    plt.hist(pens, bins=20, normed=True)
    z = np.linspace(0, 500, 200)
    plt.xlabel('thickness[nm]')
    plt.ylabel('P')
    plt.xlim(0, 2 * thickness)
    plt.plot(
        z, expon.pdf(z, *params_exp), 'r'
    )  #plt.plot(z, expon.pdf(z, *params_exp),'r',z,expon.cdf(z, *params_exp), 'g')

    plt.subplot(513)
    plt.xlim(0, thickness + 1)
    plt.xlabel('thickness[nm]')
    plt.ylabel('size[nm]')
    plt.plot(p2D[:, 0], p2D[:, 1], 'b,')

    plt.subplot(514)
    plt.ylim(-1 * 10**6, 1 * 10**6)
    plt.xlim(0, thickness + 1)
    plt.xlabel('thickness[nm]')
    plt.ylabel('size[nm]')
    plt.plot(p2De[:, 0], p2De[:, 1], 'b,')

    plt.subplot(515)

    plt.xlabel('Time[s]')
    plt.ylabel('count[1]')
    smooth = 80

    for i in np.arange(0, len(tempres)):

        tempres[i,
                1] = (np.sum(tempres[i:i + smooth, 1]) / smooth).astype(float)

    plt.ylim(0, tempres[1, 1] * 1.5)
    plt.plot(tempres[:, 0], tempres[:, 1], 'r-')

    plt.savefig(finame + 'full_tk_%dpe_%.3fea_%.3f.pdf' %
                (thickness, petest, electron_affinity))
    plt.show()
    return
Пример #4
0
def gen_velocities(v_0, v_Esc, v_E, num_object):
    """

    Generates a list of velocities

    """

    cdf_v_Esc = maxwell.cdf(v_Esc, scale=v_0 / np.sqrt(2))

    velocity_r = maxwell.ppf(np.random.rand(num_object) * cdf_v_Esc,
                             scale=v_0 / np.sqrt(2))  # kpc/yr
    velocity_theta = np.arccos(1 - 2 * np.random.rand(num_object))
    velocity_phi = 2 * np.pi * np.random.rand(num_object)

    velocity = np.zeros((3, num_object))
    velocity[0] = velocity_r * np.sin(velocity_theta) * np.cos(velocity_phi)
    velocity[1] = velocity_r * np.sin(velocity_theta) * np.sin(velocity_phi)
    velocity[2] = velocity_r * np.cos(velocity_theta)

    return velocity.T  # (N, 3)
Пример #5
0
x = np.linspace(maxwell.ppf(0.01),
                maxwell.ppf(0.99), 100)
ax.plot(x, maxwell.pdf(x),
       'r-', lw=5, alpha=0.6, label='maxwell pdf')

# Alternatively, the distribution object can be called (as a function)
# to fix the shape, location and scale parameters. This returns a "frozen"
# RV object holding the given parameters fixed.

# Freeze the distribution and display the frozen ``pdf``:

rv = maxwell()
ax.plot(x, rv.pdf(x), 'k-', lw=2, label='frozen pdf')

# Check accuracy of ``cdf`` and ``ppf``:

vals = maxwell.ppf([0.001, 0.5, 0.999])
np.allclose([0.001, 0.5, 0.999], maxwell.cdf(vals))
# True

# Generate random numbers:

r = maxwell.rvs(size=1000)

# And compare the histogram:

ax.hist(r, density=True, histtype='stepfilled', alpha=0.2)
ax.legend(loc='best', frameon=False)
plt.show()
Пример #6
0
def test_rand_velocity(sigma,
                       num_sample=10000,
                       nbins=20,
                       tolerance=1e-3,
                       seed="Dimitris",
                       plot=False,
                       save=True):
    """Test that the velocity output is sampled as a maxwellian
    Arguments:
        - sigma: argument needed to run rand_velocity
        - num_sample: number of random theta generated
        - nbins: random sampled numbers will be binned to compute
            probabilities and compare to expected values. This variable
            specifies the number of bins used.
        - tolerance: tolerance for the test
        - seed: the seed used for the random number generator
        - plot: if true, plot results
        - save: if true, saves the plot
    Returns: True if the test is succesful, False otherwise
    """
    rd.seed(seed)
    velocity_array = np.zeros(num_sample)
    for k in range(0, len(velocity_array)):
        velocity_array[k] = kicks.rand_velocity(sigma)

    #do a histogram
    vals_velocity, bins_velocity = np.histogram(velocity_array,
                                                bins=np.linspace(
                                                    0, 3 * sigma, nbins))

    prob_test = np.zeros(len(vals_velocity))

    for k in range(0, len(vals_velocity)):
        prob_test[k] = maxwell.cdf(bins_velocity[k + 1], 0,
                                   sigma) - maxwell.cdf(
                                       bins_velocity[k], 0, sigma)

    test_array = []

    for j in range(0, len(prob_test)):
        test_array = np.append(
            test_array,
            np.ones(int(round(prob_test[j] * num_sample))) * bins_velocity[j])

    if plot:
        plt.hist(velocity_array,
                 bins=np.linspace(0, 3 * sigma, nbins),
                 alpha=0.5,
                 label="function output")
        plt.hist(test_array,
                 bins=np.linspace(0, 3 * sigma, nbins),
                 alpha=0.5,
                 label="expected value")
        plt.title("velocity distribution")
        plt.xlabel("velocity value")
        plt.ylabel("distribution")
        plt.legend(loc='upper right')
        plt.show()
        plt.close()
    if save:
        plt.hist(velocity_array,
                 bins=np.linspace(0, 3 * sigma, nbins),
                 alpha=0.5,
                 label="function output")
        plt.hist(test_array,
                 bins=np.linspace(0, 3 * sigma, nbins),
                 alpha=0.5,
                 label="expected value")
        plt.title("velocity distribution")
        plt.xlabel("velocity value")
        plt.ylabel("distribution")
        plt.legend(loc='upper right')
        plt.savefig("velocity_distribution.png")
        plt.close()
    #check if the probability computed from each bin is within the tolerance
    success = True
    tolerance = max(vals_velocity) * tolerance
    for k in range(0, len(vals_velocity)):
        prob_hist = vals_velocity[k] / (sum(vals_velocity))
        if abs(prob_test[k] - prob_hist) > tolerance:
            success = False
            break

    #re-seed the random number generator
    rd.seed()

    return success
Пример #7
0
        sys.exit(0)
    temperature = float(sys.argv[1]) * kAuPerKelvin
    atom = sys.argv[2]  # 'H' or 'C'
    n = int(sys.argv[3])  # The number of generated random numbers.
    if atom == 'H':
        mass = mass_hydrogen
    elif atom == 'C':
        mass = mass_carbon
    else:
        assert(False)
    scale = numpy.sqrt(kBoltzmann * temperature / mass)
    speeds = [0.0] * n
    cumulations = [0.0] * n

    speeds[0] = maxwell.rvs(scale=scale)
    cumulations[0] = maxwell.cdf(speeds[0], scale=scale)
    for i in range(1, n):
        # bernoulli.rvs(p) = 1 in probability p, 0 in probability (1 - p).
        accelerate = (bernoulli.rvs(cumulations[i - 1]) == 0)
        if accelerate:
            speeds[i] = speeds[i - 1] * (1.0 + kDeltaTime * kAccelRatio)
        else:
            speeds[i] = max(0.0, speeds[i - 1] * (1.0 - kDeltaTime * kAccelRatio))
        # Cumulative probability P(x < speeds[i]) where x is a random variable
        # from the Maxwell distribution.
        cumulations[i] = maxwell.cdf(speeds[i], scale=scale)
    energies = map(lambda s: 0.5 * mass * (s ** 2.0), speeds)
    print 'speed [a.u.]    cumulation   energy [a.u.]'
    for i in range(n):
        print speeds[i], cumulations[i], energies[i]
    print 'temperature [a.u.]:', temperature