Exemplo n.º 1
0
def struct_radius_scatter(psi_arr, cur, den):
    hess = hessian(psi_arr)
    ntheta = 2
    nx, ny = psi_arr.shape
    psi_grad_x, psi_grad_y = gradient(psi_arr)
    bmag = np.sqrt(psi_grad_x**2 + psi_grad_y**2)
    den_x, den_y = gradient(den)
    den_grad_mag = np.sqrt(den_x**2 + den_y**2)
    surf = _cp.TopoSurface(psi_arr)
    regions = surf.get_minmax_regions()
    res = {}
    for (minmax, pss, type), region in regions.items():
        if len(region) < 50: continue
        name_2_field = {'bmag': [bmag],
                        'den': [den],
                        'cur': [cur],
                        'psi': [psi_arr],
                        'hess': [hess],
                        'den_grad': [den_grad_mag],
                        }
        for name, (field,) in name_2_field.items():
            th_sector = theta_sectors(field, minmax[0], minmax[1], region, ntheta=2)[0]
            field_radius = r_moment(th_sector['r'],th_sector['val'], th_sector['valstd'])
            res.setdefault(name, []).append(field_radius)
    return res
Exemplo n.º 2
0
def mag_shear(psi_arr):
    r'''
    computes \grad_{\perp} \bvec{B} = 
             \frac{\grad{\psi}}{2 (\grad{\psi})^2} \cdot \grad{(\grad{\psi})^2}
    '''
    psi_grad_x, psi_grad_y = gradient(psi_arr)
    psi_grad_2 = psi_grad_x**2 + psi_grad_y**2
    psi_grad_grad_x, psi_grad_grad_y = gradient(psi_grad_2)
    mag_shear = psi_grad_x * psi_grad_grad_x + psi_grad_y * psi_grad_grad_y
    return mag_shear / (2.0 * psi_grad_2)
Exemplo n.º 3
0
 def __init__(self, alpha, psi, phi, den):
     self.phi = phi
     self.psi = psi
     self.den = den
     self.alpha = alpha
     self.by, self.bx = gradient(psi)
     self.by *= -1
     self.vy, self.vx = gradient(phi)
     self.vy *= -1
     self.J = laplacian(psi)
     self.vor = laplacian(phi)
Exemplo n.º 4
0
def mag_shear_rad_profs(psi_arr):
    psi_x, psi_y = gradient(psi_arr)
    bmag = np.sqrt(psi_x**2 + psi_y**2)
    psi_arr = gaussian_filter(psi_arr, sigma=2.0, mode='wrap')
    mshear = mag_shear(psi_arr)
    surf = _cp.TopoSurface(psi_arr)
    regions = surf.get_minmax_regions()
    for (minmax, pss, type), region in regions:
        pass
    rprofs = radial_profiles(surf, threshold=25, other_arr=bmag)
    pl.ion()
    pl.figure()
    for minmax, (rprof, region) in rprofs.items():
        # minmax_flux = arr_div[minmax]
        pts, extremum_val, avg_bmags, avg_bmags_errs, avg_dists, avg_dists_errs = \
                zip(*rprof)
        # fluxes = np.abs(np.array(fluxes) - minmax_flux)
        # avg_fluxes = np.abs(np.array(avg_fluxes) - minmax_flux)
        pl.subplot(211)
        pl.plot(avg_dists, avg_bmags, 'd-')
        pl.subplot(212)
        pl.imshow(bmag)
        # pl.plot(avg_dists, avg_shear, 'd-')
        raw_input('enter to continue')
        pl.clf()
    import pdb; pdb.set_trace()
    pl.close('all')
Exemplo n.º 5
0
def total_shear(bx, by, x0, y0):
    raise RuntimeError("doesn't work; need better treatment of gradients near "
            "R=0.  Currently get wild oscillations near R=0, since gradient uses "
            "fourier transforms.")
    nx, ny = bx.shape
    br, btheta = cartesian_to_polar(bx, by, x0, y0)
    X, Y, R, theta = cartesian_to_polar_coords(x0, y0, nx, ny)
    br_by_r = br/R
    br_by_r[x0, y0] = 0.0
    br_by_r_x, br_by_r_y = gradient(br_by_r)
    bt_by_r = btheta/R
    bt_by_r[x0, y0] = 0.0
    btheta_by_r_x, btheta_by_r_y = gradient(bt_by_r)
    shear_1, _ = cartesian_to_polar(btheta_by_r_x, btheta_by_r_y, x0, y0)
    _, shear_2 = cartesian_to_polar(br_by_r_x, br_by_r_y, x0, y0)
    return shear_1 + shear_2
Exemplo n.º 6
0
def mag_shear_rad_scatter(psi_arr):
    nx, ny = psi_arr.shape
    # mshear = mag_shear(psi_arr)
    psi_grad_x, psi_grad_y = gradient(psi_arr)
    bmag = np.sqrt(psi_grad_x**2 + psi_grad_y**2)
    pl.ion()
    pl.figure()
    pl.imshow(bmag, interpolation='nearest', cmap='hot')
    surf = _cp.TopoSurface(psi_arr)
    regions = surf.get_minmax_regions()
    pl.figure()
    for (minmax, pss, type), region in regions.items():
        br, btheta = cartesian_to_polar(-psi_grad_y, psi_grad_x, minmax[0], minmax[1])
        if len(region) < 100:
            continue
        # region = expand_region(psi_arr, region, ntimes=2)
        region = expand_region_circ(psi_arr, region, minmax, extra=10.0)
        # dists, shears = \
                # flux_tube_radial_scatter(region, minmax, mshear)
        dists, bthetas = \
                flux_tube_radial_scatter(region, minmax, btheta)
        dists, bmags = \
                flux_tube_radial_scatter(region, minmax, bmag)
        # dists, fluxes = \
                # flux_tube_radial_scatter(region, minmax, psi_arr)
        pl.subplot(221)
        pl.scatter(dists, bthetas, c='b', marker='s')
        pl.grid()
        pl.title(r'$B_{\theta}$ vs. $r$')
        pl.subplot(222)
        pl.scatter(dists, bthetas/dists, c='g', marker='d')
        pl.grid()
        pl.title(r'$B_{\theta}/r$ vs. $r$')
        # nonlin_shear = (shears - bmags / dists) / dists
        # pl.scatter(dists, nonlin_shear, c='b', marker='s', label=r'$\nabla_{\perp}B$')
        pl.subplot(224)
        # psi_cpy = np.zeros_like(psi_arr)
        btheta_cpy = np.zeros_like(btheta)
        xs, ys = zip(*region)
        btheta_cpy[xs, ys] = btheta[xs, ys]
        pl.imshow(btheta_cpy, interpolation='nearest', cmap='hot')
        pl.title(r'$B_{\theta}$')
        pl.subplot(223)
        bmag_cpy = np.zeros_like(bmag)
        bmag_cpy[xs, ys] = bmag[xs, ys]
        pl.imshow(bmag_cpy, interpolation='nearest', cmap='hot')
        pl.title(r'$|B|$')
        raw_input('enter to continue')
        pl.clf()
    pl.close('all')
Exemplo n.º 7
0
def mag_shear_theta_sectors(psi_arr, cur, den, thresh=100, save_basename='field-vs-r'):
    hess = hessian(psi_arr)
    ntheta = 2
    nx, ny = psi_arr.shape
    psi_grad_x, psi_grad_y = gradient(psi_arr)
    bmag = np.sqrt(psi_grad_x**2 + psi_grad_y**2)
    den_x, den_y = gradient(den)
    den_grad_mag = np.sqrt(den_x**2 + den_y**2)
    # pl.ion()
    # pl.figure()
    # pl.imshow(bmag, interpolation='nearest', cmap='hot')
    surf = _cp.TopoSurface(psi_arr)
    regions = surf.get_minmax_regions()
    pl.figure(figsize=(9,12))
    nr = 6
    nc = 2
    ctr = 0
    for (minmax, pss, type), region in regions.items():
        if len(region) < thresh:
            continue
        ctr += 1
        print ctr
        gs = gridspec.GridSpec(nr, nc, width_ratios=[1,2], hspace=0.0)
        nbr_func = lambda t: _cp.neighbors6(t[0], t[1], nx, ny)
        lset = field_trace._level_set(psi_arr, level_val=psi_arr[pss],
                position=pss, neighbors_func=nbr_func)
        bx = -psi_grad_y
        by = psi_grad_x
        br, btheta = cartesian_to_polar(bx, by, minmax[0], minmax[1])
        region = expand_region_circ(psi_arr, region, minmax, extra=2.0)
        lset = lset.intersection(region)
        # psi
        ax = pl.subplot(gs[0])
        ax.set_title("Field & separatrix", size='x-large')
        field_region_image(ax, psi_arr, region, minmax, lset, title=r'$\psi$')
        # ax = pl.subplot2grid((nr, nc), (0, 1))
        ax = pl.subplot(gs[1])
        ax.set_title(r"Field vs. $r/\rho_s$ (id={0})".format(ctr), size='x-large')
        plot_theta_sectors(ax, psi_arr, minmax, region, ntheta, title=r'$\psi$ vs. $r/\rho_s$')
        # b_theta
        ax = pl.subplot(gs[2])
        # field_region_image(ax, btheta, region, minmax, lset, title=r'$B_{\theta}$')
        field_region_image(ax, bmag, region, minmax, lset, title=r'$|B|$')
        ax = pl.subplot(gs[3])
        # btheta_sectors = plot_theta_sectors(ax, btheta, minmax, region, ntheta, title=r'$B_{\theta}$ vs. $r/\rho_s$')
        plot_theta_sectors(ax, bmag, minmax, region, ntheta, title=r'$|B|$ vs. $r/\rho_s$')
        # b_shear
        # pl.subplot(nr, nc, 5)
        # field_region_image(btheta, region, minmax, lset, title=r'$B_{\theta}$')
        # pl.subplot(nr, nc, 6)
        # plot_sect_derivs_by_r(btheta_sectors, title=r'$\partial_{r} \frac{B_{\theta}}{r}$ vs. $r/\rho_s$')
        # den
        ax = pl.subplot(gs[4])
        field_region_image(ax, den, region, minmax, lset, title=r'$n$')
        ax = pl.subplot(gs[5])
        plot_theta_sectors(ax, den, minmax, region, ntheta, title=r'$n$ vs. $r/\rho_s$')
        # den_grad
        ax = pl.subplot(gs[6])
        field_region_image(ax, den_grad_mag, region, minmax, lset, title=r'$|\nabla n|$')
        ax = pl.subplot(gs[7])
        plot_theta_sectors(ax, den_grad_mag, minmax, region, ntheta, title=r'$|\nabla n|$ vs. $r/\rho_s$')
        # cur
        ax = pl.subplot(gs[8])
        field_region_image(ax, cur, region, minmax, lset, title=r'$J$')
        ax = pl.subplot(gs[9])
        plot_theta_sectors(ax, cur, minmax, region, ntheta, title=r'$J$ vs. $r/\rho_s$')
        # hessian
        ax = pl.subplot(gs[10])
        field_region_image(ax, hess, region, minmax, lset, title=r'$H(\psi)$', xvis=True)
        ax = pl.subplot(gs[11])
        ax.set_xlabel(r'$r/\rho_s$', size='x-large')
        plot_theta_sectors(ax, hess, minmax, region, ntheta, title=r'$H(\psi)$ vs. $r/\rho_s$', xvis=True)
        # raw_input('enter to continue')
        pl.savefig('{0}_{1:04d}.pdf'.format(save_basename, ctr))
        pl.clf()
    pl.close('all')
Exemplo n.º 8
0
def mag_shear_rad_spokes(psi_arr):
    nx, ny = psi_arr.shape
    wdist = wraparound_dist_vec(nx, ny)
    # mshear = mag_shear(psi_arr)
    psi_grad_x, psi_grad_y = gradient(psi_arr)
    bmag = np.sqrt(psi_grad_x**2 + psi_grad_y**2)
    surf = _cp.TopoSurface(psi_arr)
    regions = surf.get_minmax_regions()
    pl.ion()
    pl.figure()
    for (minmax, pss, type), region in regions.items():
        br, btheta = cartesian_to_polar(-psi_grad_y, psi_grad_x, minmax[0], minmax[1])
        if len(region) < 100:
            continue
        region = expand_region_circ(psi_arr, region, minmax, extra=10.0)
        spokes = flux_tube_radial_spokes(region, minmax, psi_arr, type)
        pl.clf()
        # max_2_bmags = []
        max_2_btheta = []
        for spoke in spokes:
            sp_arr = np.array(spoke)
            xs, ys = sp_arr[:,0], sp_arr[:,1]
            # bmags = bmag[xs, ys]
            bthetas = btheta[xs, ys]
            max_2_btheta.append((bthetas.max(), bthetas, spoke))
        max_2_btheta.sort(key=lambda x: x[0], reverse=True)
        spokes = [sp for (m, bthetas, sp) in max_2_btheta]
        btheta_cpy = np.zeros_like(btheta)
        bmag_cpy = np.zeros_like(bmag)
        br_cpy = np.zeros_like(br)
        xs, ys = zip(*region)
        btheta_cpy[xs, ys] = btheta[xs, ys]
        bmag_cpy[xs, ys] = bmag[xs, ys]
        br_cpy[xs, ys] = br[xs, ys]
        for spoke in spokes:
            sp_arr = np.array(spoke)
            xs, ys = sp_arr[:,0], sp_arr[:,1]
            dists = wdist(minmax[0], minmax[1], xs, ys)
            bthetas = btheta[xs, ys]
            # mshears = mshear[xs, ys]
            pl.subplot(221)
            pl.plot(dists, bthetas, 'o-')
            # pl.subplot(222)
            # pl.plot(dists, mshears, 's-')
            pl.subplot(222)
            pl.plot(dists[1:], bthetas[1:]/dists[1:], 'd-')
        pl.subplot(221)
        pl.grid()
        pl.title(r'$B_{\theta}$ vs. $r$')
        # pl.subplot(222)
        # pl.grid()
        # pl.title(r'$\nabla_{\perp} B$ vs. $r$')
        pl.subplot(222)
        pl.grid()
        pl.title(r'$B_{\theta}/r$ vs. $r$')
        pl.subplot(234)
        pl.imshow(btheta_cpy, interpolation='nearest', cmap='hot')
        pl.title(r'$B_{\theta}$')
        pl.subplot(235)
        pl.imshow(br_cpy, interpolation='nearest', cmap='hot')
        pl.title(r'$B_{r}$')
        pl.subplot(236)
        pl.imshow(bmag_cpy, interpolation='nearest', cmap='hot')
        pl.title(r'$|B|$')
        raw_input('enter to continue')
        pl.clf()
    pl.close('all')
Exemplo n.º 9
0
 def grad_par_v(self, arr):
     arr_x, arr_y = gradient(arr)
     return self.vx * arr_x + self.vy *arr_y
Exemplo n.º 10
0
 def grad_par_b(self, arr):
     arr_x, arr_y = gradient(arr)
     return self.bx * arr_x + self.by * arr_y