Esempio n. 1
0
# Last modified: Fri Aug 31, 2018  05:17pm
# Copyright: Bedartha Goswami <*****@*****.**>


import sys
import numpy as np
import matplotlib.pyplot as pl
import datetime as dt
import recurrence as rc


if __name__ == "__main__":
    # generate white noise data and get RP
    Xnoise = np.random.randn(500)
    Tnoise = np.arange(1, 501)
    Rnoise = rc.rp(Xnoise, m=1, tau=1, e=0.1,
                   metric="euclidean", threshold_by="frr")

    # load the Nino 3.4 data, estimate embedding parameters and get RP
    # load Nino 3.4 index data
    D = np.loadtxt("../data/enso/nino.txt", delimiter=",", skiprows=5)
    Y, M = D[:, 0], D[:, 1]
    Xnino = D[:, -1]
    # convert time info to datetime array
    Tnino = []
    for y, m in zip(Y, M):
        Tnino.append(dt.datetime(int(y), int(m), 15))
    Tnino = np.array(Tnino)
    mi, lags = rc.mi(Xnino, maxlag=100)
    i = rc.first_minimum(mi)
    tau = lags[i]
    fnn, dims = rc.fnn(Xnino, tau, maxdim=20, r=0.01)
Esempio n. 2
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def _get_data():
    """
    Estimates Lyapunov, DET, and SPL for Henon map.
    """
    # Henon map time series
    print("Henon map time series ...")
    t = np.arange(0, 10000, 1)
    a = np.linspace(1.0, 1.4, na).reshape(na, 1)
    b = 0.30
    nt = len(t)
    x, y = [np.zeros((nt, na, ns)) for i in range(2)]
    x[0, :, :] = 1E-1 * np.random.rand(na, ns)
    y[0, :, :] = 1E-1 * np.random.rand(na, ns)
    pb = _progressbar_start(max_value=nt, pbar_on=True)
    LPV = np.zeros((na, ns))
    for i in range(1, nt):
        x[i, :, :] = 1. - a * x[i - 1, :, :]**2 + y[i - 1, :, :]
        y[i, :, :] = b * x[i - 1, :, :]
        if i >= nt / 2:
            LPV[:, :] += np.log(np.fabs(-2. * a * x[i - 1, :, :]))
        _progressbar_update(pb, i)
    _progressbar_finish(pb)
    xH_eq = x[-neq:, :, :]
    LPV /= float(nt)

    # estimate embedding parameters
    print("embedding parameters ...")
    tau, m = np.ones(na, dtype="int"), 2 * np.ones(na, dtype="int")

    # DET
    print("DET ...")
    RR = 0.30
    DET = np.zeros((na, ns))
    pb = _progressbar_start(max_value=ns * na, pbar_on=True)
    k = 0
    for j in range(ns):
        for i in range(na):
            R = rc.rp(xH_eq[:, i, j],
                      m=m[i],
                      tau=tau[i],
                      e=RR,
                      norm="euclidean",
                      threshold_by="frr")
            DET[i, j] = rqa.det(R, lmin=2, hist=None, verb=False)
            del R
            _progressbar_update(pb, k)
            k += 1
    _progressbar_finish(pb)

    # SPL
    print("SPL ...")
    SPL = np.zeros((na, ns))
    pb = _progressbar_start(max_value=ns * na, pbar_on=True)
    k = 0
    for j in range(ns):
        for i in range(na):
            A = rc.rn(xH_eq[:, i, j],
                      m=m[i],
                      tau=tau[i],
                      e=RR,
                      norm="euclidean",
                      threshold_by="frr")
            G = ig.Graph.Adjacency(A.tolist(), mode=ig.ADJ_UNDIRECTED)
            pl_hist = G.path_length_hist(directed=False)
            SPL[i, j] = pl_hist.mean
            del A, G
            _progressbar_update(pb, k)
            k += 1
    _progressbar_finish(pb)

    # save output
    FN = DATPATH + "det_spl_lpv_na%d_ns%s_neq%d" % (na, ns, neq)
    np.savez(FN, DET=DET, SPL=SPL, LPV=LPV, t=t, a=a, b=b, x=x, y=y)
    print("saved to %s.npz" % FN)

    return None
Esempio n. 3
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    # fig = pl.figure(figsize=[7.480315, 3.937008])     # 190 mm wide, 100 mm tall
    wd, ht = 0.375, 0.375
    lm1, lm2 = 0.05, 0.55
    bm1, bm2 = 0.585, 0.08
    ax1 = fig.add_axes([lm1, bm1, wd, ht])
    ax2 = fig.add_axes([lm2, bm1, wd, ht])
    ax3 = fig.add_axes([lm1, bm2, wd, ht])
    ax4 = fig.add_axes([lm2, bm2, wd, ht])
    axlabfs, tiklabfs = 12, 11
    clr1, clr2, clr3 = "MediumTurquoise", "GoldenRod", "IndianRed"

    # A. Gaussian white noise RP
    print("A: Gaussian white noise ...")
    N = 500
    x = np.random.rand(N)
    R = rc.rp(x, m=1, tau=1, e=0.10, norm="euclidean", threshold_by="distance")
    ax1.imshow(R,
               cmap=pl.cm.gray_r,
               interpolation="none",
               origin="lower",
               rasterized=True)
    del R
    ax1.set_title(r"$\tau_e = 1, m_e = 1$, \varepsilon = 0.10",
                  fontsize=axlabfs)

    # B. Superposed harmonics RP
    print("B. Superposed harmonics RP ...")
    N = 500
    t = np.arange(N)
    T1, T2, T3 = 10., 50., 75.
    A1, A2, A3 = 1., 1.5, 2.
Esempio n. 4
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 e_cpr = 0.20
 e_rmd = 0.25
 pb = _progressbar_start(max_value=(N * NS), pbar_on=True)
 k = 0
 for j in range(NS):
     for i in range(N):
         # pl.clf()
         # pl.plot(X1[i], X2[i], "k.", alpha=0.5)
         # # X = rc.embed(X1[i], m=m[i], tau=tau[i])
         # # pl.plot(X[:, 0],X[:, 1])
         # pl.show()
         # sys.exit()
         R1 = rc.rp(X1[i, j, :],
                    m=m[i, j],
                    tau=tau[i, j],
                    e=e_cpr,
                    norm="euclidean",
                    threshold_by="frr",
                    normed=True)
         R2 = rc.rp(X2[i, j, :],
                    m=m[i, j],
                    tau=tau[i, j],
                    e=e_cpr,
                    norm="euclidean",
                    threshold_by="frr",
                    normed=True)
         CPR[i, j] = rqa.cpr(R1, R2)
         del R1, R2
         R1 = rc.rp(X1[i, j, :],
                    m=m[i, j],
                    tau=tau[i, j],
Esempio n. 5
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def _get_rmd():
    """Estimates the RMD between ENSO and PDO"""
    # load data
    utils._printmsg("load data ...", args.verbose)
    t, x_enso, x_pdo = _load_indices()
    x = {
        "enso": x_enso,
        "pdo": x_pdo,
    }
    names = ["enso", "pdo"]

    # recurrence plot parameters
    EPS = 0.30
    thrby = "frr"

    # embedding parameters
    utils._printmsg("embedding parameters ...", args.verbose)
    n = len(t)
    m, tau = {}, {}
    R = {}
    maxlag = 150
    maxdim = 20
    r_fnn = 0.0010
    for name in names:
        if args.verbose: print("\t for %s" % name.upper())
        # get embedding parameters
        ## get mi
        mi, mi_lags = rc.mi(x[name], maxlag, pbar_on=False)
        # mi, mi_lags = rc.acf(x[name], maxlag)
        mi_filt, _ = utils.boxfilter(mi, filter_width=3, estimate="mean")
        try:
            tau[name] = rc.first_minimum(mi_filt)
        except ValueError:
            tau[name] = 1
        ## FNN
        fnn, dims = rc.fnn(x[name],
                           tau[name],
                           maxdim=maxdim,
                           r=r_fnn,
                           pbar_on=False)
        m[name] = dims[rc.first_zero(fnn)]
    # take the maximum delay and the maximum embedding dimension
    tau = np.max([tau["enso"], tau["pdo"]]).astype("int")
    m = np.max([m["enso"], m["pdo"]]).astype("int")

    # get surrogates
    utils._printmsg("surrogates ...", args.verbose)
    ns = args.nsurr
    SURR = {}
    params = {
        "m": m,
        "tau": tau,
        "eps": EPS,
        "norm": "euclidean",
        "thr_by": thrby,
        "tol": 2.
    }
    for name in names:
        utils._printmsg("\t for %s" % name.upper(), args.verbose)
        # SURR[name] = rc.surrogates(x[name], ns, "iaaft", verbose=args.verbose)
        SURR[name] = rc.surrogates(x[name],
                                   ns,
                                   "twins",
                                   params,
                                   verbose=args.verbose)

    # get RMD for original data
    utils._printmsg("RMD for original data ...", args.verbose)
    ws, ss = args.window_size, args.step_size
    nw = int(np.floor(float(n - ws) / float(ss)))
    tm = np.empty(nw, dtype="object")
    for name in names:
        R[name] = rc.rp(
            x[name],
            m=m,
            tau=tau,
            e=EPS,
            norm="euclidean",
            threshold_by=thrby,
        )
    rmd = np.zeros(nw)
    pb = _progressbar_start(max_value=nw, pbar_on=args.verbose)
    for i in range(nw):
        start = i * ss
        end = start + ws
        Rw_enso = R["enso"][start:end, start:end]
        Rw_pdo = R["pdo"][start:end, start:end]
        rmd[i] = rqa.rmd(Rw_enso, Rw_pdo)
        tm[i] = t[start] + (t[end] - t[start]) / 2
        _progressbar_update(pb, i)
    _progressbar_finish(pb)

    # get RMD for surrogate data
    utils._printmsg("RMD for surrogates ...", args.verbose)
    Rs = {}
    rmdsurr = np.zeros((ns, nw), dtype="float")
    pb = _progressbar_start(max_value=ns, pbar_on=args.verbose)
    for k in range(ns):
        for name in names:
            xs = SURR[name][k]
            Rs[name] = rc.rp(
                xs,
                m=m,
                tau=tau,
                e=EPS,
                norm="euclidean",
                threshold_by=thrby,
            )
        for i in range(nw):
            start = i * ss
            end = start + ws
            Rsw_enso = Rs["enso"][start:end, start:end]
            Rsw_pdo = Rs["pdo"][start:end, start:end]
            rmdsurr[k, i] = rqa.rmd(Rsw_enso, Rsw_pdo)
        _progressbar_update(pb, k)
    _progressbar_finish(pb)

    # get each individual array out of dict to avoid  NumPy import error
    SURR_enso = SURR["enso"]
    SURR_pdo = SURR["pdo"]
    tm = np.array([date.toordinal() for date in tm])

    # save output
    EPS = int(EPS * 100)
    FN = DATPATH + "rmd_WS%d_SS%d_EPS%dpc_NSURR%d" \
                   % (ws, ss, EPS, ns)
    np.savez(
        FN,
        rmd=rmd,
        tm=tm,
        rmdsurr=rmdsurr,
        SURR_enso=SURR_enso,
        SURR_pdo=SURR_pdo,
    )
    if args.verbose: print("output saved to: %s.npz" % FN)

    return None
Esempio n. 6
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def _get_spl():
    """
    Estimates the average shortest path length SPL for the indices.
    """
    # load data
    utils._printmsg("load data ...", args.verbose)
    t, x_enso, x_pdo = _load_indices()
    x = {
        "enso": x_enso,
        "pdo": x_pdo,
    }
    names = ["enso", "pdo"]

    # get surrogates
    utils._printmsg("iAAFT surrogates ...", args.verbose)
    ns = args.nsurr
    SURR = {}
    for name in names:
        utils._printmsg("\t for %s" % name.upper(), args.verbose)
        SURR[name] = rc.surrogates(x[name], ns, "iaaft", verbose=args.verbose)

    # recurrence plot parameters
    EPS, LMIN = 0.30, 3
    thrby = "frr"

    # get SPL for original data
    utils._printmsg("SPL for original data ...", args.verbose)
    n = len(t)
    ws, ss = args.window_size, args.step_size
    nw = int(np.floor(float(n - ws) / float(ss)))
    tm = np.empty(nw, dtype="object")
    m, tau = {}, {}
    A = {}
    maxlag = 150
    maxdim = 20
    r_fnn = 0.0010
    SPL = {}
    for name in names:
        if args.verbose: print("\t for %s" % name.upper())
        # get embedding parameters
        ## get mi
        mi, mi_lags = rc.mi(x[name], maxlag, pbar_on=False)
        # mi, mi_lags = rc.acf(x[name], maxlag)
        mi_filt, _ = utils.boxfilter(mi, filter_width=3, estimate="mean")
        try:
            tau[name] = rc.first_minimum(mi_filt)
        except ValueError:
            tau[name] = 1
        ## FNN
        fnn, dims = rc.fnn(x[name],
                           tau[name],
                           maxdim=maxdim,
                           r=r_fnn,
                           pbar_on=False)
        m[name] = dims[rc.first_zero(fnn)]
        A[name] = rc.rn(
            x[name],
            m=m[name],
            tau=tau[name],
            e=EPS,
            norm="euclidean",
            threshold_by=thrby,
        )
        A_ = A[name]
        G_ = ig.Graph.Adjacency(A_.tolist(), mode=ig.ADJ_UNDIRECTED)
        nw = len(tm)
        spl = np.zeros(nw)
        pb = _progressbar_start(max_value=nw, pbar_on=args.verbose)
        for i in range(nw):
            start = i * ss
            end = start + ws
            Gw = G_.subgraph(vertices=G_.vs[start:end])
            pl_hist = Gw.path_length_hist(directed=False)
            spl[i] = pl_hist.mean
            tm[i] = t[start] + (t[end] - t[start]) / 2
            _progressbar_update(pb, i)
        _progressbar_finish(pb)
        SPL[name] = spl

    # get SPL for surrogate data
    utils._printmsg("SPL for surrogates ...", args.verbose)
    SPLSURR = {}
    for name in names:
        utils._printmsg("\tfor %s" % name.upper(), args.verbose)
        xs = SURR[name]
        y = np.diff(xs, axis=0)
        splsurr = np.zeros((ns, nw), dtype="float")
        pb = _progressbar_start(max_value=ns, pbar_on=args.verbose)
        for k in range(ns):
            As = rc.rp(
                xs[k],
                m=m[name],
                tau=tau[name],
                e=EPS,
                norm="euclidean",
                threshold_by=thrby,
            )
            Gs = ig.Graph.Adjacency(As.tolist(), mode=ig.ADJ_UNDIRECTED)
            for i in range(nw):
                start = i * ss
                end = start + ws
                Gw = Gs.subgraph(vertices=Gs.vs[start:end])
                pl_hist = Gw.path_length_hist(directed=False)
                splsurr[k, i] = pl_hist.mean
            _progressbar_update(pb, k)
        _progressbar_finish(pb)
        SPLSURR[name] = splsurr

    # get each individual array out of dict to avoid  NumPy import error
    SPL_enso = SPL["enso"]
    SPL_pdo = SPL["pdo"]
    SPLSURR_enso = SPLSURR["enso"]
    SPLSURR_pdo = SPLSURR["pdo"]
    SURR_enso = SURR["enso"]
    SURR_pdo = SURR["pdo"]
    tm = np.array([date.toordinal() for date in tm])

    # save output
    EPS = int(EPS * 100)
    FN = DATPATH + "spl_WS%d_SS%d_EPS%dpc_LMIN%d_NSURR%d" \
                   % (ws, ss, EPS, LMIN, ns)
    np.savez(FN,
             SPL_enso=SPL_enso,
             SPL_pdo=SPL_pdo,
             SPLSURR_enso=SPLSURR_enso,
             SPLSURR_pdo=SPLSURR_pdo,
             SURR_enso=SURR_enso,
             SURR_pdo=SURR_pdo,
             tm=tm)
    if args.verbose: print("output saved to: %s.npz" % FN)

    return None
Esempio n. 7
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def _get_det():
    """
    Estimates the determinism DET for the indices.
    """
    # load data
    utils._printmsg("load data ...", args.verbose)
    t, x_enso, x_pdo = _load_indices()
    x = {
        "enso": x_enso,
        "pdo": x_pdo,
    }
    names = ["enso", "pdo"]

    # get surrogates
    utils._printmsg("iAAFT surrogates ...", args.verbose)
    ns = args.nsurr
    SURR = {}
    for name in names:
        utils._printmsg("\t for %s" % name.upper(), args.verbose)
        SURR[name] = rc.surrogates(x[name], ns, "iaaft", verbose=args.verbose)

    # recurrence plot parameters
    EPS, LMIN = 0.30, 3
    thrby = "frr"

    # get DET for original data
    utils._printmsg("DET for original data ...", args.verbose)
    n = len(t)
    ws, ss = args.window_size, args.step_size
    nw = int(np.floor(float(n - ws) / float(ss)))
    tm = np.empty(nw, dtype="object")
    m, tau = {}, {}
    R = {}
    maxlag = 150
    maxdim = 20
    r_fnn = 0.0010
    DET = {}
    for name in names:
        if args.verbose: print("\t for %s" % name.upper())
        # get embedding parameters
        ## get mi
        mi, mi_lags = rc.mi(x[name], maxlag, pbar_on=False)
        # mi, mi_lags = rc.acf(x[name], maxlag)
        mi_filt, _ = utils.boxfilter(mi, filter_width=3, estimate="mean")
        try:
            tau[name] = rc.first_minimum(mi_filt)
        except ValueError:
            tau[name] = 1
        ## FNN
        fnn, dims = rc.fnn(x[name],
                           tau[name],
                           maxdim=maxdim,
                           r=r_fnn,
                           pbar_on=False)
        m[name] = dims[rc.first_zero(fnn)]
        R[name] = rc.rp(
            x[name],
            m=m[name],
            tau=tau[name],
            e=EPS,
            norm="euclidean",
            threshold_by=thrby,
        )
        R_ = R[name]
        nw = len(tm)
        det = np.zeros(nw)
        pb = _progressbar_start(max_value=nw, pbar_on=args.verbose)
        for i in range(nw):
            start = i * ss
            end = start + ws
            Rw = R_[start:end, start:end]
            det[i] = rqa.det(Rw, lmin=LMIN, hist=None, verb=False)
            tm[i] = t[start] + (t[end] - t[start]) / 2
            _progressbar_update(pb, i)
        _progressbar_finish(pb)
        DET[name] = det

    # get DET for surrogate data
    utils._printmsg("DET for surrogates ...", args.verbose)
    DETSURR = {}
    for name in names:
        utils._printmsg("\tfor %s" % name.upper(), args.verbose)
        xs = SURR[name]
        y = np.diff(xs, axis=0)
        detsurr = np.zeros((ns, nw), dtype="float")
        pb = _progressbar_start(max_value=ns, pbar_on=args.verbose)
        for k in range(ns):
            Rs = rc.rp(
                xs[k],
                m=m[name],
                tau=tau[name],
                e=EPS,
                norm="euclidean",
                threshold_by=thrby,
            )
            for i in range(nw):
                start = i * ss
                end = start + ws
                Rw = Rs[start:end, start:end]
                detsurr[k, i] = rqa.det(Rw, lmin=LMIN, hist=None, verb=False)
            _progressbar_update(pb, k)
        _progressbar_finish(pb)
        DETSURR[name] = detsurr

    # get each individual array out of dict to avoid  NumPy import error
    DET_enso = DET["enso"]
    DET_pdo = DET["pdo"]
    DETSURR_enso = DETSURR["enso"]
    DETSURR_pdo = DETSURR["pdo"]
    SURR_enso = SURR["enso"]
    SURR_pdo = SURR["pdo"]
    tm = np.array([date.toordinal() for date in tm])

    # save output
    EPS = int(EPS * 100)
    FN = DATPATH + "det_WS%d_SS%d_EPS%dpc_LMIN%d_NSURR%d" \
                   % (ws, ss, EPS, LMIN, ns)
    np.savez(FN,
             DET_enso=DET_enso,
             DET_pdo=DET_pdo,
             DETSURR_enso=DETSURR_enso,
             DETSURR_pdo=DETSURR_pdo,
             SURR_enso=SURR_enso,
             SURR_pdo=SURR_pdo,
             tm=tm)
    if args.verbose: print("output saved to: %s.npz" % FN)

    return None
Esempio n. 8
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def _get_data():
    """
    Estimates Lyapunov, DET, and SPL for Henon map.
    """
    # Henon map time series
    print("Henon map time series ...")
    t = np.arange(0, 10000, 1)
    a = np.linspace(1.28, 1.32, na).reshape(na, 1)
    j, k = (1 * na) / 8, ns / 2
    print "a = ", a[j]
    # sys.exit()
    b = 0.30
    nt = len(t)
    x, y = [np.zeros((nt, na, ns)) for i in range(2)]
    x[0, :, :] = 1E-2 * np.random.rand(na, ns)
    y[0, :, :] = 1E-2 * np.random.rand(na, ns)
    pb = _progressbar_start(max_value=nt, pbar_on=True)
    LPV = np.zeros((na, ns))
    for i in range(1, nt):
        x[i, :, :] = 1. - a * x[i - 1, :, :]**2 + y[i - 1, :, :]
        y[i, :, :] = b * x[i - 1, :, :]
        if i >= nt / 2:
            LPV[:, :] += np.log(np.fabs(-2. * a * x[i - 1, :, :]))
        _progressbar_update(pb, i)
    _progressbar_finish(pb)
    xH_eq = x[-neq:, :, :]
    LPV /= float(nt)

    print("RP ...")
    RR = 0.30
    y = xH_eq[:, j, k].flatten()
    R = rc.rp(y, m=2, tau=1, e=RR, norm="euclidean", threshold_by="frr")
    DET = rqa.det(R, lmin=2, hist=None, verb=False)
    print DET
    print("plot...")
    pl.subplot(211)
    pl.plot(y, alpha=0.5)
    pl.subplot(212)
    pl.imshow(R, cmap=pl.cm.gray_r, origin="lower", interpolation="none")
    pl.show()
    sys.exit()

    print("plot data ...")
    xplot = np.zeros((na, neq * ns))
    for i in range(na):
        xplot[i] = xH_eq[:, i, :].flatten()
    print("plot ...")
    fig = pl.figure(figsize=[21., 12.], facecolor="none")
    ax = fig.add_axes([0.10, 0.10, 0.80, 0.80])
    ax.plot(a,
            xplot,
            "o",
            ms=1.00,
            alpha=0.25,
            rasterized=True,
            mfc="k",
            mec="none")
    print("prettify ...")
    ax.tick_params(labelsize=14, size=8)
    ax.tick_params(size=5, which="minor")
    # ax.set_xticks(np.arange(1.0, 1.401, 0.05), minor=False)
    # ax.set_xticks(np.arange(1.0, 1.401, 0.01), minor=True)
    ax.grid(which="both")
    # ax.set_xlim(1.0, 1.4)
    print("save figure ...")
    FN = "../plots/" + __file__[2:-3] + ".png"
    fig.savefig(FN, rasterized=True, dpi=100)
    print("figure saved to: %s" % FN)
    sys.exit()

    # estimate embedding parameters
    print("embedding parameters ...")
    tau, m = np.ones(na, dtype="int"), 2 * np.ones(na, dtype="int")

    # DET
    print("DET ...")
    RR = 0.25
    DET = np.zeros((na, ns))
    pb = _progressbar_start(max_value=ns * na, pbar_on=True)
    k = 0
    for j in range(ns):
        for i in range(na):
            R = rc.rp(xH_eq[:, i, j],
                      m=m[i],
                      tau=tau[i],
                      e=RR,
                      norm="euclidean",
                      threshold_by="frr")
            DET[i, j] = rqa.det(R, lmin=2, hist=None, verb=False)
            del R
            _progressbar_update(pb, k)
            k += 1
    _progressbar_finish(pb)

    # SPL
    print("SPL ...")
    SPL = np.zeros((na, ns))
    pb = _progressbar_start(max_value=ns * na, pbar_on=True)
    k = 0
    for j in range(ns):
        for i in range(na):
            A = rc.rn(xH_eq[:, i, j],
                      m=m[i],
                      tau=tau[i],
                      e=RR,
                      norm="euclidean",
                      threshold_by="frr")
            G = ig.Graph.Adjacency(A.tolist(), mode=ig.ADJ_UNDIRECTED)
            pl_hist = G.path_length_hist(directed=False)
            SPL[i, j] = pl_hist.mean
            del A, G
            _progressbar_update(pb, k)
            k += 1
    _progressbar_finish(pb)

    # save output
    FN = DATPATH + "det_spl_lpv_na%d_ns%s_neq%d" % (na, ns, neq)
    np.savez(FN, DET=DET, SPL=SPL, LPV=LPV, t=t, a=a, b=b, x=x, y=y)
    print("saved to %s.npz" % FN)

    return None