Exemple #1
0
def exp_fit():
    from scipy.optimize import curve_fit
    for name, energies in zip(*parse_evolution()):
        if not "Trial energy" in name: continue

        # Fit energy vs iteration to exponential decay
        # using initial guess informed by data
        to_fit = lambda n, a, b, c: a + b * np.exp(-n / c)
        p0 = [energies[-1], energies[0] - energies[-1], len(energies) / 4]
        bounds = [[min(energies), -np.inf, 1],
                  [max(energies), np.inf, 10 * len(energies)]]

        x = np.array([float(i) for i in range(0, len(energies))])
        par, cov = curve_fit(to_fit, x, energies, p0, bounds=bounds)
        residuals = [e - to_fit(n, *par) for n, e in enumerate(energies)]
        print(par[0], "+/-", np.std(residuals))

        if "plot" in sys.argv:
            import matplotlib.pyplot as plt

            # Plot the data, fit and residuals
            plt.subplot(211)
            plt.plot(energies, label="DMC")
            xs = np.linspace(0, len(energies), 1000)
            ys = [to_fit(x, *par) for x in xs]
            plt.plot(xs, ys, label="Fit")
            plt.ylabel("Trial energy (Hartree)")
            plt.legend()

            plt.subplot(212)
            plt.plot(residuals)
            plt.axhline(0, color="black")
            plt.ylabel("Residuals (Hartree)")

            plt.show()
Exemple #2
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def reblocked():
    es = None
    for name, energies in zip(*parse_evolution()):
        if not "Trial energy" in name: continue
        es = energies
    if es is None: raise Exception("Could not find the trial energies!")
    start = int(sys.argv[2])

    # Get the energies after the provided
    # start iteration, and their mean
    es = es[start:]
    energy = np.mean(es)

    # Init arrays
    block_errors = []
    block_error_errors = []

    # Loop over blocking transformation number
    blocking_transform = 0
    while True:

        # Work out the block length, if it is greater than
        # the total length, break
        block_length = 2**blocking_transform
        blocking_transform += 1
        if block_length > len(es):
            break

        # Work out the energies of each block
        block_energies = []
        offset = 0
        while offset < len(es):
            block_energies.append(np.mean(es[offset:offset + block_length]))
            offset += block_length

        # Work out the reblocked error + the error on that
        block_err = np.std(block_energies) / np.sqrt(len(block_energies))
        block_errors.append(block_err)
        block_err_err = block_err / np.sqrt(2 * (len(block_energies) - 1))
        block_error_errors.append(block_err_err)

    if len(block_errors) == 0:
        return

    # Plot vs blocking number if requested
    if "plot" in sys.argv:
        import matplotlib.pyplot as plt

        plt.errorbar(range(len(block_errors)),
                     block_errors,
                     yerr=block_error_errors)
        plt.xlabel("Blocking transformation number")
        plt.ylabel("Reblocked errror (Ha)")
        plt.show()

    print("{0} +/- {1}".format(energy, max(block_errors)))
Exemple #3
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def average():
    for name, energies in zip(*parse_evolution()):
        if not "Trial energy" in name: continue
        start = int(sys.argv[2])

        energies = energies[start:]
        print(np.mean(energies), " +/- ",
              np.std(energies) / np.sqrt(len(energies)))
        if "plot" in sys.argv:
            import matplotlib.pyplot as plt

            plt.plot(energies)
            plt.axhline(np.mean(energies), color="black")
            plt.show()
Exemple #4
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def multi_exp_fit(exponents=3):
    from scipy.optimize import curve_fit
    for name, energies in zip(*parse_evolution()):
        if not "Trial energy" in name: continue
        to_fit = lambda n, a, b, c: a + b * np.exp(-n / c)

        residuals = np.array(energies)
        parameters = []
        for i in range(0, exponents):
            p0 = [
                residuals[-1], residuals[0] - residuals[-1],
                len(residuals) / 4
            ]
            bounds = [[min(residuals), -np.inf, 1],
                      [max(residuals), np.inf, 10 * len(residuals)]]
            par, cov = curve_fit(to_fit,
                                 range(0, len(residuals)),
                                 residuals,
                                 p0,
                                 bounds=bounds)
            fit = [to_fit(n, *par) for n in range(0, len(residuals))]
            residuals -= fit
            parameters.append(par)

        model = lambda n: sum(to_fit(n, *p) for p in parameters)
        print(model(10e10))

        if "plot" in sys.argv:
            import matplotlib.pyplot as plt

            fit = [model(n) for n in range(0, len(energies))]
            ext = [model(n) for n in range(0, len(energies) * 10)]
            plt.subplot(211)
            plt.plot(energies)
            plt.plot(fit)
            plt.plot(ext)
            plt.subplot(212)
            plt.plot(np.array(energies) - np.array(fit))
            plt.axhline(0, color="black")
            plt.show()
Exemple #5
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def pi_weighted():
    for name, energies in zip(*parse_evolution()):
        if not "Trial energy" in name: continue
        start = int(sys.argv[2])
        corr = int(sys.argv[3])
        energies = energies[start:]

        f = open("progress")
        lines = f.read().split("\n")
        f.close()

        for l in lines:
            if "DMC timestep" in l:
                tau = float(l.split(":")[-1])
                break

        mean_e = np.mean(energies)
        pi = lambda m: np.product(
            [np.exp(-tau * (e - mean_e)) for e in energies[m - corr:m]])
        estimate = sum([pi(m) * energies[m] for m in range(0, len(energies))])
        estimate /= sum([pi(m) for m in range(0, len(energies))])
        print(estimate)
Exemple #6
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def pop_correction():
    for name, data in zip(*parse_evolution()):
        if "Population" in name: pop = np.array(data)
        if "Trial energy" in name: energy = np.array(data)

    half = int(len(energy) / 2)
    energy = energy[half:]
    pop = pop[half:]
    pop_f = pop - 10000

    from scipy.optimize import minimize
    to_min = lambda a: np.std(energy + a * pop_f)
    res = minimize(to_min, x0=[0.0])
    energy_corrected = energy + res.x * pop_f

    e1 = np.mean(energy)
    de1 = np.std(energy) / np.sqrt(float(len(energy)))
    e2 = np.mean(energy_corrected)
    de2 = np.std(energy_corrected) / np.sqrt(float(len(energy_corrected)))

    import matplotlib.pyplot as plt

    plt.subplot(311)
    plt.plot(pop_f)

    plt.subplot(312)
    lab = "{0} +/- {1}".format(e1, de1)
    plt.plot(energy, label=lab)
    plt.legend()

    plt.subplot(313)
    lab = "{0} +/- {1}".format(e2, de2)
    plt.plot(energy_corrected, label=lab)
    plt.legend()

    plt.show()
Exemple #7
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        if val == "lithium": e_targ = -7.47807
        elif val == "beryllium": e_targ = -14.667353
        elif val == "boron": e_targ = -24.65386608
        elif val == "helium_triplet": e_targ = -2.1753
        elif val == "helium_gs": e_targ = -2.9037
        else: e_targ = float(val)
        break

v_targ = None
for arg in sys.argv:
    if arg.startswith("-v="):
        v_targ = float(arg.split("=")[-1])
        break

# Read in the evolution data
y_axes, data = parse_evolution()

i_include = []
for a in sys.argv:
    try:
        i_include.append(int(a))
    except:
        pass

if len(i_include) > 0:
    new_data = []
    new_yaxes = []
    for i in range(0, len(data)):
        if not i in i_include: continue
        new_data.append(data[i])
        new_yaxes.append(y_axes[i])