Ejemplo n.º 1
0
    def test_simu_hawkes_force_simulation(self):
        """...Test force_simulation parameter of SimuHawkes
        """
        diverging_kernel = [[HawkesKernelExp(2, 3)]]
        hawkes = SimuHawkes(kernels=diverging_kernel, baseline=[1],
                            verbose=False)
        hawkes.end_time = 10

        msg = '^Simulation not launched as this Hawkes process is not ' \
              'stable \(spectral radius of 2\). You can use ' \
              'force_simulation parameter if you really want to simulate it$'
        with self.assertRaisesRegex(ValueError, msg):
            hawkes.simulate()

        msg = "^This process has already be simulated until time 0.000000$"
        with self.assertWarnsRegex(UserWarning, msg):
            hawkes.end_time = 0
            hawkes.force_simulation = True
            hawkes.simulate()
Ejemplo n.º 2
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    def test_hawkes_set_baseline_piecewiseconstant(self):
        """...Test Hawkes process baseline set with time and value arrays
        """
        baselines = [[1., 2., 1.5, 4.],
                     [2., 1.5, 4., 1.]]
        hawkes = SimuHawkes(baseline=baselines, period_length=3.5,
                            kernels=self.kernels, verbose=False)

        hawkes.end_time = 10
        hawkes.simulate()
        self.assertGreater(hawkes.n_total_jumps, 1)
Ejemplo n.º 3
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    def simulate_hawkes(self, model_name):
        self.model_name = model_name

        def y_func_pos(t_values):
            y_values = 0.02 * np.exp(-t_values)
            return y_values

        def y_func_neg(t_values):
            y_values = -0.1 * np.exp(-t_values)
            return y_values

        if model_name == 'hawkes_neg':
            y_func = y_func_neg
        elif model_name == 'hawkes_pos':
            y_func = y_func_pos

        t_values = np.linspace(0, 101, 100)
        y_values = y_func(t_values)
        tf = TimeFunction([t_values, y_values],
                          inter_mode=TimeFunction.InterLinear,
                          dt=0.1)

        tf_kernel = HawkesKernelTimeFunc(tf)

        N_enodes = self.G_e2n.number_of_nodes()  # regarded as 'N_enodes' types

        base_int = 0.2
        baselines = [base_int for i in range(N_enodes)]
        kernels = [[] for i in range(N_enodes)]
        for i in range(N_enodes):
            for j in range(N_enodes):
                if i == j:
                    # kernels[i].append(HawkesKernel0())
                    kernels[i].append(HawkesKernelExp(.1, 4))  # self influence
                else:
                    if self.G_e2n.has_edge(self.idx_elabel_map[i],
                                           self.idx_elabel_map[j]):
                        kernels[i].append(tf_kernel)
                    else:
                        kernels[i].append(HawkesKernel0())

        hawkes = SimuHawkes(kernels=kernels,
                            baseline=baselines,
                            verbose=False,
                            seed=self.seed)
        hawkes.threshold_negative_intensity(allow=True)

        run_time = 100
        hawkes.end_time = run_time
        hawkes.simulate()
        timestamps = hawkes.timestamps

        self.save(timestamps, self.model_name)
Ejemplo n.º 4
0
 def test_hawkes_set_baseline_timefunction(self):
     """...Test Hawkes process baseline set with TimeFunction
     """
     t_values = [0.5, 1., 2., 3.5]
     y_values_1 = [1., 2., 1.5, 4.]
     y_values_2 = [2., 1.5, 4., 1.]
     timefunction1 = TimeFunction((t_values, y_values_1))
     timefunction2 = TimeFunction((t_values, y_values_2))
     hawkes = SimuHawkes(baseline=[timefunction1, timefunction2],
                         kernels=self.kernels, verbose=False)
     hawkes.end_time = 10
     hawkes.simulate()
     self.assertGreater(hawkes.n_total_jumps, 1)
t_values = np.array([0, 1, 1.5], dtype=float)
y_values = np.array([0, .2, 0], dtype=float)
tf1 = TimeFunction([t_values, y_values],
                   inter_mode=TimeFunction.InterConstRight,
                   dt=0.1)
kernel_1 = HawkesKernelTimeFunc(tf1)

t_values = np.array([0, .1, 2], dtype=float)
y_values = np.array([0, .4, -0.2], dtype=float)
tf2 = TimeFunction([t_values, y_values],
                   inter_mode=TimeFunction.InterLinear,
                   dt=0.1)
kernel_2 = HawkesKernelTimeFunc(tf2)

hawkes = SimuHawkes(kernels=[[kernel_1, kernel_1],
                             [HawkesKernelExp(.07, 4), kernel_2]],
                    baseline=[1.5, 1.5],
                    verbose=False,
                    seed=23983)

run_time = 40
dt = 0.01
hawkes.track_intensity(dt)
hawkes.end_time = run_time
hawkes.simulate()

fig, ax = plt.subplots(hawkes.n_nodes, 1, figsize=(14, 8))
plot_point_process(hawkes, t_max=20, ax=ax)

plt.show()
def g2(t):
    return np.cos(np.pi * (t / 10 + 1)) + 1.1


t_values = np.linspace(0, 20, 1000)
u_values = [(0.007061, 0.001711), (0.005445, 0.003645), (0.003645, 0.005445),
            (0.001790, 0.007390)]

hawkes = SimuHawkes(baseline=[1e-5, 1e-5], seed=1093, verbose=False)
for i, j in itertools.product(range(2), repeat=2):
    u1, u2 = u_values[2 * i + j]
    y_values = g1(t_values) * u1 + g2(t_values) * u2
    kernel = HawkesKernelTimeFunc(t_values=t_values, y_values=y_values)
    hawkes.set_kernel(i, j, kernel)

hawkes.end_time = end_time
hawkes.simulate()
ticks = hawkes.timestamps

# And then perform estimation with two basis kernels
kernel_support = 20
n_basis = 2

em = HawkesBasisKernels(kernel_support,
                        n_basis=n_basis,
                        kernel_size=kernel_size,
                        C=C,
                        n_threads=4,
                        max_iter=max_iter,
                        verbose=False,
                        ode_tol=1e-5)
support = 2000

hawkes = SimuHawkes(kernels=[[
    HawkesKernelPowerLaw(multiplier[0], cutoff, exponent, support),
    HawkesKernelPowerLaw(multiplier[1], cutoff, exponent, support)
],
                             [
                                 HawkesKernelPowerLaw(multiplier[2], cutoff,
                                                      exponent, support),
                                 HawkesKernelPowerLaw(multiplier[3], cutoff,
                                                      exponent, support)
                             ]],
                    baseline=[0.05, 0.05],
                    seed=382,
                    verbose=False)
hawkes.end_time = 50000
hawkes.simulate()

e = HawkesConditionalLaw(claw_method="log",
                         delta_lag=0.1,
                         min_lag=0.002,
                         max_lag=100,
                         quad_method="log",
                         n_quad=50,
                         min_support=0.002,
                         max_support=support,
                         n_threads=-1)

e.incremental_fit(hawkes.timestamps)
e.compute()