Beispiel #1
0
def adiabatic(tp, BW, beta, resolution=resolution):
    ''' Make Adiabatic Pulse Shape based on Hyperbolic Secant pulse

    .. math::
        \\text{sech} \\left( \\beta (t - \\frac{t_p}{2}) \\right) ^{1+i(\pi BW / \\beta)}

    Args:
        tp (float): pulse length
        BW (float): pulse bandwidth
        beta (float): truncation factor
        resolution (float): pulse resolution

    Returns:
        tuple: tuple containing:

            t (*numpy.ndarray*): Time axes

            pulse (*numpy.ndarray*): Pulse shape
    '''

    beta = float(beta) / tp
    mu = np.pi * BW / beta

    t = np.r_[0.:tp:resolution]

    pulse = (np.sech(beta * (t - 0.5 * tp)))**(1. + 1.j * mu)

    return t, pulse
Beispiel #2
0
def adiabatic(peakb1 = 0.2, bw = 2000, beta = 1000., T = 0.01, Ts = 0.00001, blochsim = True):
    T = 2*np.round(T/Ts/2)*Ts
    N = T/Ts
    
    t = np.arange(Ts, T, Ts) - np.round(N/2)*Ts #time from -t/2 to t/2
    
    b1 = peakb1 * np.sech(beta*t)
    freq = bw/2 * np.tanh(beta*t)
    phase = np.cumsum(freq)*2*np.pi*Ts
    phase = phase-phase(np.round(N/2))  #zero phase half-way
    phase = np.mod(phase+np.pi,2*np.pi)-np.pi  #limit to -pi to pi
    
    if blochsim:
        t = t-t[0]  #start t at 0 for plots
        figure(1)
        print('Adiabatic silver-hoult pulse (beta = '+str(beta)+' Hz) ')
        subplot(3,1,1)
        plot(t,b1); xlable('Time(s)'); ylabel('B1(G)')
        title(tt)
        subplot(3,1,2)
        plot(t,phase); xlabel('Time(s)'); ylabel('Phase(rad)')
        subplot(3,1,3)
        plot(t,freq); xlabel('Time(s)'); ylabel('Freq(hz)')
        
        #add in 
        if 0:
            gr = 0*b1
            tp = Ts
            t1 = 0.6; t2 = 0.1
            df = np.arange(-3*bw, 3*bw, bw/20.)
            dp = 0
            mode = 0
            mx,my,mz = bloch(0)  # finish this
Beispiel #3
0
    def __init__(self, wavenumber=1, depth=1, length=10, g=1):
        self.wavenumber = k = wavenumber
        self.depth = h = depth

        self.frequency = sigma = np.sqrt(g * k * np.tanh(k * h))

        self.group_velocity = cg = g / (2 * sigma) * (k * h * np.sech(k * h)**2 + np.tanh(k * h))
        self.S = g * k**2 / sigma**2 * cg * (1 + np.tanh(k * h)**2)
Beispiel #4
0
def dv(x):
        
    pot = 'Eckart'
    
    if pot == 'Morse':
    
        a, x0, De = 1.02, 1.4, 0.176
    
        d = (1.0-np.exp(-a*(x-x0)))
    
        v0 = De*d**2
    
        ddv = 2.0 * De * (-d*np.exp(-a*((x-x0)))*a**2 + (np.exp(-a*(x-x0)))**2*a**2)
        
    elif pot == 'Double_well':
        
        eta = 1.3544 
        v0 = x**4/16.0/eta - x**2/2.0 
        ddv = 3./4./eta * x**2 - 1.0 
    
    elif pot == 'Harmonic':
        
        v0 = x**2/2.0
        ddv = 1.0 
        
    elif pot == 'Eckart':
        
        D = 16.0
        #a = 1.3624d0 
        a = 1.0
        v0 = D/np.cosh(a*x)**2
        dv = -2.0 * a * D * np.sech(a*x)**2 * np.tanh(a*x) 
        ddv = 6.0*D*a**2*np.sinh(a*x)**2/np.cosh(a*x)**4-2.*D*a**2/np.cosh(a*x)**2

    
    else:
        print("ERROR: there is no such potential.")
            
    return v0,dv,ddv
Beispiel #5
0
def forcing(t, u, perturbation_params=[1, 0.15, 0.5]):
    """
    Returns vector field for a perturbation at time t, for an array of points in phase space.
    Number of model parameters: 3. perturbation_params = [perturbation_type, amplitude, frequency]
    Functional form: v = (, ), with u = (x, y)
    
    Parameters
    ----------
    t : float
        fixed time-point of vector field, for all points in phase space.
        
    u : array_like, shape(n,)
        points in phase space to determine vector field at time t.
        
    perturbation_params : list of floats, [perturbation_type, amplitude, frequency]
        vector field parameters
    
    Returns
    -------
    v : array_like, shape(n,)
        vector field corresponding to points u, in phase space at time t
    """
    x, y = u.T
    perturbation = np.zeros(u.shape)

    # Perturbation parameters
    perturbation_type, amplitude, freq = perturbation_params

    if perturbation_type == 1:
        perturbation = perturbation + np.array(
            [0, amplitude * np.sin(freq * t)])
    elif perturbation_type == 2:
        perturbation = perturbation + np.array(
            [0, amplitude * np.sech(t) * np.sin(freq * t)])

    return perturbation
Beispiel #6
0
	def d_tan_hyperbolic(input_stimulus):
		# Returns the derivative of the tan_hyperbolic fxn.
		
		d_hyp_value = (np.sech(input_stimulus)) ** 2
		return d_hype_value
def tanhgrad(z):
    gard = np.sech(z)**2
    return grad
Beispiel #8
0
def dtanh(x, scale=1.0):
    return scale * (np.sech(x)**2)
Beispiel #9
0
def make_kdv_dataset(name='kdv',
                     test_split=0.1,
                     device='cpu',
                     verbose=False,
                     long_data=False):
    torch.set_default_dtype(torch.float64)
    torch.backends.cudnn.deterministic = True
    torch.backends.cudnn.benchmark = False
    rng = np.random.get_state()
    np.random.seed(1)

    ndata = 100
    M = 50
    width = 10.
    dt = 0.001
    N = 500
    a = -6.
    b = 1.
    if long_data:
        np.random.seed(100)
        ndata = 5
        test_split = 1.0
        N = 5000
    t_eval = np.arange(0, N + 1) * dt
    x = width * np.arange(M) / M

    np.sech = lambda a: 1 / np.cosh(a)
    kdv1d = KdV1d(width=width, ndiv=M, a=a, b=b, device='cpu')
    u_results = []
    for i in range(ndata):
        if verbose:
            print('generating KdV dataset,', i, '/', ndata, end='\r')
        k1, k2 = np.random.uniform(0.5, 2.0, 2)
        d1 = np.random.uniform(0.2, 0.3, 1)
        d2 = d1 + np.random.uniform(0.2, 0.5, 1)
        x = width * np.arange(M) / M
        u0 = 0
        u0 += (-6. / a) * 2 * k1**2 * np.sech(k1 * (x - width * d1))**2
        u0 += (-6. / a) * 2 * k2**2 * np.sech(k2 * (x - width * d2))**2
        shift = np.random.randint(0, M)
        u0 = np.concatenate([u0[M:], u0[:M]], axis=-1)
        if np.random.randint(0, 2) == 1:
            u0 = u0[::-1].copy()
        u_result = kdv1d.dvdmint(u0, t_eval)
        u_result = u_result.reshape(-1, 1, M)
        u_results.append(u_result)
    u_results = np.stack(u_results, axis=0)

    data = {}
    dudt = kdv1d.dudt(u_results.reshape(-1, 1, M)).reshape(u_results.shape)
    energy = kdv1d.get_energy(u_results.reshape(-1, 1, M)).reshape(
        u_results.shape[:2])
    ntrain = int(ndata * (1 - test_split))
    data['u'] = u_results[:ntrain]
    data['test_u'] = u_results[ntrain:]
    data['dudt'] = dudt[:ntrain]
    data['test_dudt'] = dudt[ntrain:]
    data['energy'] = energy[:ntrain]
    data['test_energy'] = energy[ntrain:]
    data['dt'] = dt
    data['t_eval'] = t_eval
    data['dx'] = kdv1d.dx
    data['M'] = M
    data['model'] = kdv1d

    np.random.set_state(rng)
    return data
#put in dataframe
training_df = pd.DataFrame(columns=["f_1", "f_2", "labels", "outputs"])
training_df.f_1 = [x for x in vectors[0]]
training_df.f_2 = [x for x in vectors[1]]
training_df.labels = labels

#%% Definitions

GAMMA = 0.01

# output layer
g_output = lambda a: 1 / (1 + np.e**-a)
g_output_deriv = lambda a: g_output(a) * (1 - g_output(a))

# hidden layer
g_hidden = lambda b: np.tanh(b)
g_hidden_deriv = lambda b: np.sech(b)**2

y_fun = lambda a: g_hidden(a)
z_fun = lambda b: g_output(b)

E = lambda y, t: 0.5 * (y - t)**2

delta_w_output = lambda y, z, t, b: GAMMA * (t - z) * g_output_deriv(b) * y

delta_w_hidden = lambda x, z, t, w, a, b: GAMMA * (t - z) * g_hidden_deriv(
    b) * w * g_hidden_deriv(a) * x

hidden_w = [0, 0]
output_w = [0, 0]
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/E X P E R I M E N T.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/untitled1.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/E X P E R I M E N T.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
P
alpha
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/E X P E R I M E N T.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
alpha
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/E X P E R I M E N T.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
alpha
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/E X P E R I M E N T.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')

## ---(Sat Nov 17 21:15:55 2018)---
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/Navier Stokes.Eq_Fahrudin Nugroho.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/untitled0.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
import numpy as np
np.sech(0)
np.cosh(0)
1/(np.sech(0))
1/(np.cosh(0))
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/untitled0.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/Simple3Dplot.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/Laplace.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/untitled7.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/Heat.eq_Spectral.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/untitled7.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')

## ---(Tue Nov 20 07:40:16 2018)---
runfile('C:/Users/Reizkian Yesaya/.spyder-py3/FFT.py', wdir='C:/Users/Reizkian Yesaya/.spyder-py3')
import numpy as np
np.fft.fft(100)
np.fft.fft(y)
Beispiel #12
0
def d_tanh(input_stimulus, slope_param=1.0):

    # Returns the derivative of the tan_hyperbolic fxn.
    d_hyp_value = slope_param * np.square((np.sech(input_stimulus)))
    return d_hype_value
Beispiel #13
0
def dtanh(z):
    return np.sech(z)**2
Beispiel #14
0
 def nonlinTanh(self, x, deriv=False):
     if (deriv == True):
         return 1 / (np.sech(x)**2)
     return np.tanh(x)