Exemple #1
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def optimal_weights(k, xi, **kwargs):
  r"""Compute the optimal weights for a 2k-1 order WENO scheme
  corresponding to the reconstruction points in *xi*.

  The coefficients are stored as SymPy variables in a dictionary
  indexed according to ``w[l,r]``.  That is

  .. math::

    f(\xi^l) \approx \sum_r w^r f^r

  for each :math:`l` from 0 to ``len(xi)``.
  """

  n = len(xi)

  c   = reconstruction_coefficients(k, xi, **kwargs)
  c2k = reconstruction_coefficients(2*k-1, xi, **kwargs)

  omega = [ sym('omega%d' % r) for r in range(k) ]
  varpi = { 'n': n, 'k': k }
  split = { 'n': n }

  for l in range(n):

    # use first k eqns since weight system is overdetermined
    eqns = []
    for j in range(k):
      rmin, rmax = max(0, (k-1)-j), min(k-1, 2*(k-1)-j)
      terms = [ omega[r] * c[l, r, r-(k-1)+j] for r in range(rmin, rmax+1) ]
      eqns.append(sum(terms) - c2k[l, k-1, j])

    # XXX: Should make sure that when mpmath.mpf's are passed in
    # (in xi), that the solution obtained above is a high
    # precision solution.

    sol = sympy.solve(eqns, omega)

    # now check all 2*k-1 eqns to make sure the weights work out properly
    for j in range(2*k-1):
      rmin, rmax = max(0, (k-1)-j), min(k-1, 2*(k-1)-j)
      terms = [ omega[r] * c[l, r, r-(k-1)+j] for r in range(rmin, rmax+1) ]
      eqn = sum(terms) - c2k[l, k-1, j]
      err = eqn.subs(sol)
      if abs(err) > 1e-10:
        raise ValueError("optimal weight %d failed with error %s" % (j, err))

    # set weight or split as appropriate
    split[l] = min(sol.values()) < 0
    for r in range(k):
      if split[l]:
        w  = sol[omega[r]]
        wp = (w + 3*abs(w))/2
        wm = wp - w
        varpi[l, r] = (wp, wm)
      else:
        varpi[l, r] = sol[omega[r]]

  return varpi, split
Exemple #2
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    def symbolic_equation(self, n):
        T = sym(' '.join(f"T_{i}" for i in range(n)))
        J = sym(' '.join(f"J_{i}" for i in range(n)))

        A = [
            sym('A_0'),
        ]
        for i in range(n):
            A.append(A[-1] + J[i] * T[i])

        S = [
            sym('S_0'),
        ]
        for i in range(n):
            S.append(S[-1] + A[i] * T[i] + J[i] * T[i]**2 / 2)

        return T, J, A, S
Exemple #3
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def jiang_shu_smoothness_coefficients(k):
  r"""Compute the Jiang-Shu smoothness coefficients for a 2k-1 order
  WENO scheme.

  The coefficients are stored as SymPy variables in a dictionary
  indexed according to ``beta[r, m, n]``.  That is

  .. math::

    \sigma^r = \sum_{m=1}^{2k-1} \sum_{n=1}^{2k-1}
      \beta_{r,m,n}\, \overline{f}_{i-k+m}\, \overline{f}_{i-k+n}.
  """

  x, dx, xi = sym('x'), sym('dx'), sym('x')

  # build arrays of cell boundaries and cell averages
  xs = [ j*dx               for j in range(-k+1, k+1) ]
  fs = [ sym('f[i%+d]' % j) for j in range(-k+1, k)   ]

  beta = { 'k': k }

  # compute smoothness coefficients for each left shift r
  for r in range(k):
    p = ppi(xs[k-1-r:2*k-r], fs[k-1-r:2*k-1-r]).diff(x)

    # sum of L^2 norms of derivatives
    s = 0
    for j in range(1, k):
      pp = sympy.diff(p, xi, j)**2
      pp = pp.as_poly(x)
      pp = pp.integrate(x)
      pp = dx**(2*j-1) * ( pp.subs(x, xs[k]) - pp.subs(x, xs[k-1]) )
      s += pp.expand()

    # pick out coefficients
    for m in range(k):
      for n in range(m, k):
        c = s.coeff(fs[k-1-r+m]*fs[k-1-r+n])
        if c is not None:
          beta[r, m, n] = c

  return beta
Exemple #4
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def jiang_shu_smoothness_coefficients(k):
    r"""Compute the Jiang-Shu smoothness coefficients for a 2k-1 order
  WENO scheme.

  The coefficients are stored as SymPy variables in a dictionary
  indexed according to ``beta[r, m, n]``.  That is

  .. math::

    \sigma^r = \sum_{m=1}^{2k-1} \sum_{n=1}^{2k-1}
      \beta_{r,m,n}\, \overline{f}_{i-k+m}\, \overline{f}_{i-k+n}.
  """

    x, dx, xi = sym('x'), sym('dx'), sym('x')

    # build arrays of cell boundaries and cell averages
    xs = [j * dx for j in range(-k + 1, k + 1)]
    fs = [sym('f[i%+d]' % j) for j in range(-k + 1, k)]

    beta = {'k': k}

    # compute smoothness coefficients for each left shift r
    for r in range(k):
        p = ppi(xs[k - 1 - r:2 * k - r], fs[k - 1 - r:2 * k - 1 - r]).diff(x)

        # sum of L^2 norms of derivatives
        s = 0
        for j in range(1, k):
            pp = sympy.diff(p, xi, j)**2
            pp = pp.as_poly(x)
            pp = pp.integrate(x)
            pp = dx**(2 * j - 1) * (pp.subs(x, xs[k]) - pp.subs(x, xs[k - 1]))
            s += pp.expand()

        # pick out coefficients
        for m in range(k):
            for n in range(m, k):
                c = s.coeff(fs[k - 1 - r + m] * fs[k - 1 - r + n])
                if c is not None:
                    beta[r, m, n] = c

    return beta
Exemple #5
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def reconstruction_coefficients(k, xi, d=0):
  r"""Compute the reconstruction coefficients for a 2k-1 order WENO
  scheme corresponding to the reconstruction points in *xi*.

  The reconstruction points in *xi* should in :math:`[-1, 1]`.  This
  interval is then mapped to the cell :math:`[x_{i-1/2}, x_{i+1/2}]`.

  The returned coefficients are stored as SymPy variables in a
  dictionary indexed according to ``c[l, r, j]``.  That is

  .. math::

    f^r(\xi_l) \approx \sum_j c^{l,r}_j \, f_{i-r+j}

  for each :math:`l` from 0 to ``len(xi)``.
  """

  i, n, x, dx  = k-1, len(xi), sym('x'), sym('dx')

  # build arrays of cell boundaries and cell averages
  xs = [ j*dx               for j in range(-k+1, k+1) ]
  fs = [ sym('f[i%+d]' % j) for j in range(-k+1, k)   ]

  c = { 'n': n, 'k': k, 'd': d }

  # compute reconstruction coefficients for each left shift r
  for l, r in product(range(n), range(k)):
    p = ppi(xs[i-r:i-r+k+1], fs[i-r:i-r+k]).diff(x, d+1)

    for j in range(k):
      z = _pt(xs[i], xs[i+1], xi[l])
      c[l, r, j] = p.subs(x, z).expand().coeff(fs[i-r+j])

      if c[l, r, j] is None:
        c[l, r, j] = 0

      c[l, r, j] *= dx**d

  return c
Exemple #6
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def reconstruction_coefficients(k, xi, d=0):
    r"""Compute the reconstruction coefficients for a 2k-1 order WENO
  scheme corresponding to the reconstruction points in *xi*.

  The reconstruction points in *xi* should in :math:`[-1, 1]`.  This
  interval is then mapped to the cell :math:`[x_{i-1/2}, x_{i+1/2}]`.

  The returned coefficients are stored as SymPy variables in a
  dictionary indexed according to ``c[l, r, j]``.  That is

  .. math::

    f^r(\xi_l) \approx \sum_j c^{l,r}_j \, f_{i-r+j}

  for each :math:`l` from 0 to ``len(xi)``.
  """

    i, n, x, dx = k - 1, len(xi), sym('x'), sym('dx')

    # build arrays of cell boundaries and cell averages
    xs = [j * dx for j in range(-k + 1, k + 1)]
    fs = [sym('f[i%+d]' % j) for j in range(-k + 1, k)]

    c = {'n': n, 'k': k, 'd': d}

    # compute reconstruction coefficients for each left shift r
    for l, r in product(range(n), range(k)):
        p = ppi(xs[i - r:i - r + k + 1], fs[i - r:i - r + k]).diff(x, d + 1)

        for j in range(k):
            z = _pt(xs[i], xs[i + 1], xi[l])
            c[l, r, j] = p.subs(x, z).expand().coeff(fs[i - r + j])

            if c[l, r, j] is None:
                c[l, r, j] = 0

            c[l, r, j] *= dx**d

    return c
Exemple #7
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def theta_penalty(p):
    """
    unweighted
    """
    a0, a1, a2, a3 = get_coeff(p)
    start, goal = posture()
    tht0 = start[2]
    sf = p[2]
    s = sym('s')
    thtsf = tht0 + (a3 / 4) * (s**4) + (a2 / 3) * (s**3) + (a1 / 2) * (
        s**2) + a0 * s
    thtf = goal[2]
    tht_penalty = abs(thtsf.subs(s, sf) - thtf)
    return (thtsf, tht_penalty)
Exemple #8
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    def get_sympy(self):

        n = self.n

        px_lst = sym(' '.join(f'P^{i}_x' for i in range(n)))
        py_lst = sym(' '.join(f'P^{i}_y' for i in range(n)))

        q_lst = self.p_coef(n)

        x0 = 0
        y0 = 0
        for i in range(n):
            x0 += q_lst[i] * px_lst[i] * (t)**i * (1 - t)**(n - i - 1)
            y0 += q_lst[i] * py_lst[i] * (t)**i * (1 - t)**(n - i - 1)

        x1 = sympy.diff(x0, t)
        y1 = sympy.diff(y0, t)
        x2 = sympy.diff(x1, t)
        y2 = sympy.diff(y1, t)

        s0 = (x1 * y2 - y1 * x2) / (x1**2 + y1**2)**sympy.Rational(3, 2)

        return x0, y0, s0
Exemple #9
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def y_penalty(p):
    a0, a1, a2, a3 = get_coeff(p)
    start, goal = posture()
    s = sym('s')
    #need to call theta_penalty
    thtsf, th_penalty = theta_penalty(p)
    sf = p[2]
    y0 = start[1]
    ysf = y0 + (sf/24)*( \
    sin(thtsf.subs(s,0)) + 4*sin(thtsf.subs(s,sf/8))  + \
    2*sin(thtsf.subs(s,(2*sf)/8)) + 4*sin(thtsf.subs(s,(3*sf)/8)) + \
    2*sin(thtsf.subs(s,(4*sf)/8)) + 4*sin(thtsf.subs(s,(5*sf)/8)) + \
    2*sin(thtsf.subs(s,(6*sf)/8)) + 4*sin(thtsf.subs(s,(7*sf)/8)) + \
    sin(thtsf.subs(s,(8*sf)/8)))

    yf = goal[1]
    y_p = abs(ysf - yf)
    return y_p
Exemple #10
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def x_penalty(p):
    a0, a1, a2, a3 = get_coeff(p)
    start, goal = posture()
    s = sym('s')
    #need to call theta_penalty
    thtsf, th_penalty = theta_penalty(p)
    sf = p[2]
    x0 = start[0]
    xsf = x0 + (sf/24)*( \
    cos(thtsf.subs(s,0)) + 4*cos(thtsf.subs(s,sf/8))  + \
    2*cos(thtsf.subs(s,(2*sf)/8)) + 4*cos(thtsf.subs(s,(3*sf)/8)) + \
    2*cos(thtsf.subs(s,(4*sf)/8)) + 4*cos(thtsf.subs(s,(5*sf)/8)) + \
    2*cos(thtsf.subs(s,(6*sf)/8)) + 4*cos(thtsf.subs(s,(7*sf)/8)) + \
    cos(thtsf.subs(s,(8*sf)/8)))

    xf = goal[0]
    x_p = abs(xsf - xf)
    return x_p
Exemple #11
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def polynomial_interpolator(x, y):
    """Build a symbolic polynomial that interpolates the points (x_i, y_i).

  The returned polynomial is a function of the SymPy variable x.
  """

    k, xi = len(x), sym('x')

    sum_i = 0
    for i in range(k):
        ns = range(k)
        ns.remove(i)

        num, den = 1, 1
        for n in ns:
            num *= xi - x[n]
            den *= x[i] - x[n]

        sum_i += num / den * y[i]

    return sum_i
Exemple #12
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    def target_pos(self):
        """
			compute the expected position reached at the end of the trajbang3
		"""
        t = sym('t')

        pos_n = 0
        spd_n = self.s0
        acc_n = self.a0

        for c, d in zip(self.cmd, self.dur):
            jrk_s = c
            acc_s = sympy.integrate(jrk_s, t) + acc_n
            spd_s = sympy.integrate(acc_s, t) + spd_n
            pos_s = sympy.integrate(spd_s, t) + pos_n
            acc_n = acc_s.subs({'t': d})
            spd_n = spd_s.subs({'t': d})
            pos_n = pos_s.subs({'t': d})
        self.pg = pos_n

        return self.pg
Exemple #13
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def polynomial_interpolator(x, y):
  """Build a symbolic polynomial that interpolates the points (x_i, y_i).

  The returned polynomial is a function of the SymPy variable x.
  """

  k, xi = len(x), sym('x')

  sum_i = 0
  for i in range(k):
    ns = range(k)
    ns.remove(i)

    num, den = 1, 1
    for n in ns:
      num *= xi   - x[n]
      den *= x[i] - x[n]

    sum_i += num / den * y[i]

  return sum_i
Exemple #14
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def optimal_weights(k, xi, **kwargs):
    r"""Compute the optimal weights for a 2k-1 order WENO scheme
  corresponding to the reconstruction points in *xi*.

  The coefficients are stored as SymPy variables in a dictionary
  indexed according to ``w[l,r]``.  That is

  .. math::

    f(\xi^l) \approx \sum_r w^r f^r

  for each :math:`l` from 0 to ``len(xi)``.
  """

    n = len(xi)

    c = reconstruction_coefficients(k, xi, **kwargs)
    c2k = reconstruction_coefficients(2 * k - 1, xi, **kwargs)

    omega = [sym('omega%d' % r) for r in range(k)]
    varpi = {'n': n, 'k': k}
    split = {'n': n}

    for l in range(n):

        # use first k eqns since weight system is overdetermined
        eqns = []
        for j in range(k):
            rmin, rmax = max(0, (k - 1) - j), min(k - 1, 2 * (k - 1) - j)
            terms = [
                omega[r] * c[l, r, r - (k - 1) + j]
                for r in range(rmin, rmax + 1)
            ]
            eqns.append(sum(terms) - c2k[l, k - 1, j])

        # XXX: Should make sure that when mpmath.mpf's are passed in
        # (in xi), that the solution obtained above is a high
        # precision solution.

        sol = sympy.solve(eqns, omega)

        # now check all 2*k-1 eqns to make sure the weights work out properly
        for j in range(2 * k - 1):
            rmin, rmax = max(0, (k - 1) - j), min(k - 1, 2 * (k - 1) - j)
            terms = [
                omega[r] * c[l, r, r - (k - 1) + j]
                for r in range(rmin, rmax + 1)
            ]
            eqn = sum(terms) - c2k[l, k - 1, j]
            err = eqn.subs(sol)
            if abs(err) > 1e-10:
                raise ValueError("optimal weight %d failed with error %s" %
                                 (j, err))

        # set weight or split as appropriate
        split[l] = min(sol.values()) < 0
        for r in range(k):
            if split[l]:
                w = sol[omega[r]]
                wp = (w + 3 * abs(w)) / 2
                wm = wp - w
                varpi[l, r] = (wp, wm)
            else:
                varpi[l, r] = sol[omega[r]]

    return varpi, split
Exemple #15
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def bending_energy(p):
    a0, a1, a2, a3 = get_coeff(p)
    s = sym('s')
    result = integrate((a0 + a1 * s + a2 * (s**2) + a3 * (s**3))**2, s)
    return result
Exemple #16
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#!/usr/bin/env python3

import math

import numpy as np
import matplotlib.pyplot as plt

import sympy
from sympy import symbols as sym

t = sym('t')


class Bezier():
    def __init__(self, arg=None):

        self.p_lst = None
        if arg is None:
            self.n = None

        try:
            self.set_p(arg)
        except TypeError:
            self.n = int(arg)

    def set_p(self, p_lst):
        self.p_lst = list(p_lst)
        self.n = len(p_lst)

        self.val = dict()
        for i, (a, b) in enumerate(self.p_lst):
Exemple #17
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    obj = be + tht_p + x_p + y_p
    first = diff(obj, p1)
    second = diff(obj, p2)
    third = diff(obj, p4)
    return (first, second, third)


def spiral_planner():
    start, goal = posture()
    p = [1, 1, 3]  #the p values will originally come from optimization
    # objective_function(p)
    be = bending_energy(p)
    _, tht_p = theta_penalty(p)
    x_p = x_penalty(p)
    y_p = y_penalty(p)

    objective_value = be + tht_p + x_p + y_p

    print(objective_value)
    print(be)


tic = time.time()
p1 = sym('p1')
p2 = sym('p2')
p4 = sym('p4')
p = [p1, p2, p4]
jacobian(p)
toc = time.time()
print(toc - tic)
Exemple #18
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def compute_3(jm, am, a0, s0, sg, debug=False):
    # calcul la commande en jrk nécessaire pour:
    #  * rejoindre la vitesse sg à partir de la vitesse s0
    #  * avec une accélération finale nulle

    J_m, A_m, A_0, S_0, S_g = sym('J_m A_m A_0 S_0 S_g')

    val = {
        'J_m': jm,
        'A_m': am,
        'A_0': a0,
        'S_0': s0,
        'S_g': sg,
    }

    # l'aire totale de l'accélération doit être égale au delta de vitesse
    Q_d = S_g - S_0

    if float(A_0.subs(val)) == 0.0:
        # départ à accélération nulle
        s = math.copysign(1.0, sg - s0)

        Q_m = A_m**2 / J_m

        if float(abs(Q_d).subs(val)) <= float(Q_m.subs(val)):
            # CASE 2
            # on a pas le temps d'atteindre l'accélération max
            # time_for_acc = math.sqrt(abs(aire_target) / jm)
            T_a = sympy.sqrt(abs(Q_d) / J_m)

            bch = "B" + sign_var(s)
            cmd = [s, -s]
            dur = [T_a, T_a]
        else:
            # CASE 1
            # on atteind l'accélération maximale
            # time_triangle = am / jm
            T_t = A_m / J_m
            # aire_restante_pour_rectangle = abs(aire_target) - aire_maxi_triangle
            Q_r = abs(Q_d) - Q_m
            # time_rectangle = aire_restante_pour_rectangle / am
            T_r = Q_r / A_m

            bch = "A" + sign_var(s)
            cmd = [s, 0, -s]
            dur = [T_t, T_r, T_t]
    else:
        # mais pour revenir à zero, il nous faut au moins un triangle, dont l'aire est égale à
        T_n = abs(A_0) / J_m
        Q_n = T_n * A_0 / 2
        Q_c = Q_d - Q_n

        s = math.copysign(1.0, a0)

        if 0 < float((Q_c * Q_n).subs(val)):
            # l'aire restante est un triangle possiblement tronqué de taille maxi :
            Q_u = abs(A_m**2 - A_0**2) / (J_m)
            if float(abs(Q_c).subs(val)) <= float(Q_u.subs(val)):
                D = 4 * A_0**2 + 4 * J_m * abs(Q_c)
                T_b = (-2 * abs(A_0) + sympy.sqrt(D)) / (2 * J_m)

                bch = "C" + sign_var(s)
                cmd = [s, -s, -s]
                dur = [T_b, T_b, T_n]
            else:
                T_s = (abs(Q_c) - Q_u) / A_m

                bch = "D" + sign_var(s)
                cmd = [s, 0, -s, -s]
                dur = [
                    abs(A_m - abs(A_0)) / J_m, T_s,
                    abs(A_m - abs(A_0)) / J_m, T_n
                ]

        elif float((Q_c * Q_n).subs(val)) < 0:
            # le reste n'est pas dans le même sens que le petit triangle
            # c'est un triangle et pas un trapèze, si l'aire restante est inférieure à :
            Q_s = A_m * A_m / J_m
            if float(Q_s.subs(val)) < float(abs(Q_c).subs(val)):
                Q_g = abs(Q_c) - Q_s

                bch = "E" + sign_var(s)
                cmd = [-s, -s, 0, s]
                dur = [T_n, A_m / J_m, Q_g / A_m, A_m / J_m]
            else:
                bch = "F" + sign_var(s)
                cmd = [-s, -s, s]
                dur = [
                    T_n,
                    sympy.sqrt(abs(Q_c) / J_m),
                    sympy.sqrt(abs(Q_c) / J_m)
                ]
        else:
            bch = "G0"
            cmd = [
                -s,
            ]
            dur = [
                T_n,
            ]

    return bch, cmd, dur, val
Exemple #19
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from pwn import *
from sympy.parsing.sympy_parser import parse_expr
from sympy import Eq, Symbol as sym, solve

#Connect to server
r = remote("misc.chal.csaw.io", 9002)
while (True):
    try:
        #Get data from server
        x = r.recv()
        lines = x.split("\n")
        equation = lines[-2]
        #Split equation into L.H.S and R.H.S
        parts = equation.split("=")
        if len(parts) > 1:
            X = sym('X')
            lhs = parts[0].strip()
            rhs = parts[-1].strip()
            #Use parse_expr to convert the two sides of the equation from string to a format accepted by sympy
            lhs = parse_expr(lhs)
            rhs = parse_expr(rhs)
            #Solve equation
            eqa = Eq(lhs, rhs)
            res = solve(eqa)
            print "Result:", res
            #sympy returns answers of 0 and 1 as Boolean type which causes error while sending, handling these use cases
            if str(res) == "True":
                r.send(str(float(1)) + "\n")
            if str(res) == "False":
                r.send(str(float(0)) + "\n")
            #Sending equation
Exemple #20
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import numpy as np
import sympy
from sympy import RealNumber as Real, symbols as sym, diff as d

DIMENSION = 2
x = sym('x y')

CONTRAV = True
COV = False


class Index:
    def __init__(self, name):
        self.name = name.strip('-')
        self.contrv = (name[0] != '-')

    @staticmethod
    def new(names):
        return tuple([Index(i) for i in names.split()])

    def __repr__(self):
        return self.name if self.contrv else '-' + self.name

    def __neg__(self):
        if self.contrv:
            return Index('-' + self.name)
        else:
            return Index(self.name)

    def __eq__(self, other):
        return self.name == other.name and self.contrv == other.contrv
Exemple #21
0
    def _compute_analytic(self, unfold=False):
        """
			this implementation keep symbolic expressions as much as possible, and details all cases
		"""
        bch_lst = list()

        jm, am, a0, s0, sg = self.jm, self.am, self.a0, self.s0, self.sg
        val = self.val

        def u_abs(exp):
            if unfold:
                p = exp.subs(val)
                if 0 <= p:
                    bch_lst.append('+')
                    return exp
                else:
                    bch_lst.append('-')
                    return -exp
            else:
                return abs(exp)

        # creation des symboles
        J_m, A_m, A_0, S_0, S_g = sym('J_m A_m A_0 S_0 S_g')

        # l'intégrale de l'accélération doit être égale au delta de vitesse
        Q_d = S_g - S_0

        if float(A_0.subs(val)) == 0.0:
            # cas d'un départ à accélération nulle, le sens est donné par le delta de vitesse
            s = 1 if (Q_d).subs(val) >= 0 else -1

            if unfold:
                bch_lst.append(sign_var(s))

            # l'integrale d'une acceleration triangulaire, partant de zero et atteignant l'accéleration maximale
            Q_m = A_m**2 / J_m
            if float(abs(Q_d).subs(val)) <= float(Q_m.subs(val)):
                # BRANCH B
                bch_lst = [
                    "B",
                ] + bch_lst
                # on a pas le temps d'atteindre l'accélération maximale
                # le temps de montée jusqu'à l'accélération requise (pour une aire inférieure ou égale à Q_m)
                T_a = sympy.sqrt(u_abs(Q_d) / J_m)
                cmd = [s, -s]
                dur = [T_a, T_a]
            else:
                # BRANCH A
                bch_lst = [
                    "A",
                ] + bch_lst
                # on a le temps d'atteindre l'accélération maximale, il y a donc une phase plateau à jerk nul
                # time_triangle = am / jm
                T_t = A_m / J_m
                # aire_restante_pour_rectangle = abs(aire_target) - aire_maxi_triangle
                Q_r = u_abs(Q_d) - Q_m
                # time_rectangle = aire_restante_pour_rectangle / am
                T_r = Q_r / A_m
                cmd = [s, 0, -s]
                dur = [T_t, T_r, T_t]
        else:
            s = 1 if a0 >= 0 else -1

            if unfold:
                bch_lst.append(sign_var(s))

            # mais pour revenir à zero, il nous faut au moins un triangle, dont l'aire est égale à
            T_n = u_abs(A_0) / J_m
            Q_n = T_n * A_0 / 2
            Q_c = Q_d - Q_n
            if 0 < float((Q_c * Q_n).subs(val)):
                # l'aire restante est un triangle possiblement tronqué de taille maxi :
                Q_u = u_abs(A_m**2 - A_0**2) / (J_m)
                if float(abs(Q_c).subs(val)) <= float(Q_u.subs(val)):
                    bch_lst = [
                        "C",
                    ] + bch_lst
                    D = 4 * A_0**2 + 4 * J_m * u_abs(Q_c)
                    T_b = (-2 * u_abs(A_0) + sympy.sqrt(D)) / (2 * J_m)
                    cmd = [s, -s]
                    dur = [T_b, T_b + T_n]
                else:
                    bch_lst = [
                        "D",
                    ] + bch_lst
                    T_s = (u_abs(Q_c) - Q_u) / A_m
                    Q_t = u_abs(A_m - u_abs(A_0))
                    cmd = [s, 0, -s]
                    dur = [Q_t / J_m, T_s, Q_t / J_m + T_n]
            elif float((Q_c * Q_n).subs(val)) < 0:
                # le reste n'est pas dans le même sens que le petit triangle
                # c'est un triangle et pas un trapèze, si l'aire restante est inférieure à :
                Q_s = A_m * A_m / J_m
                if float(Q_s.subs(val)) < float(abs(Q_c).subs(val)):
                    bch_lst = [
                        "E",
                    ] + bch_lst
                    Q_g = u_abs(Q_c) - Q_s
                    cmd = [-s, 0, s]
                    dur = [T_n + A_m / J_m, Q_g / A_m, A_m / J_m]
                else:
                    bch_lst = [
                        "F",
                    ] + bch_lst
                    T_e = sympy.sqrt(u_abs(Q_c) / J_m)
                    cmd = [-s, s]
                    dur = [T_n + T_e, T_e]
            else:
                bch_lst = [
                    f"G",
                ] + bch_lst
                cmd = [
                    -s,
                ]
                dur = [
                    T_n,
                ]

        bch = ''.join(bch_lst)

        return cmd, dur, bch
Exemple #22
0
def objective_function(p):
    """
    BENDING ENERGY + PENALTIES
    """
    #bending energy
    p1 = p[0]
    p2 = p[1]
    p4 = p[2]
    start, goal = posture()
    p0 = start[-1]
    p3 = goal[-1]

    a0 = p0
    a1 = -(5.5 * p0 - 9 * p1 + 4.5 * p2 - p3) / p4
    a2 = (9 * p0 - 22.5 * p1 + 18 * p2 - 4.5 * p3) / (p4**2)
    a3 = (-4.5 * p0 - 13.5 * p1 + 13.5 * p2 - 4.5 * p3) / (p4**2)

    s = sym('s')
    result = integrate((a0 + a1 * s + a2 * (s**2) + a3 * (s**3))**2)
    bending_energy = result.subs(s, p4) - result.subs(s, 0)

    #weights
    alpha = 0.1
    beta = 0.1
    gamma = 0.1

    #theta penalty
    tht0 = start[2]
    sf = p4
    thtsf = tht0 + (a3 / 4) * (s**4) + (a2 / 3) * (s**3) + (a1 / 2) * (
        s**2) + a0 * s  #obtained symbolic
    thtf = goal[2]
    theta_penalty = gamma * abs(thtsf.subs(s, sf) - thtf)

    #x_penalty
    x0 = start[0]
    xsf = x0 + (sf/24)*( \
    cos(float(thtsf.subs(s,0))) + 4*cos(float(thtsf.subs(s,sf/8)))  + \
    2*cos(float(thtsf.subs(s,(2*sf)/8))) + 4*cos(float(thtsf.subs(s,(3*sf)/8))) + \
    2*cos(float(thtsf.subs(s,(4*sf)/8))) + 4*cos(float(thtsf.subs(s,(5*sf)/8))) + \
    2*cos(float(thtsf.subs(s,(6*sf)/8))) + 4*cos(float(thtsf.subs(s,(7*sf)/8))) + \
    cos(float(thtsf.subs(s,(8*sf)/8))))

    xf = goal[0]
    x_penalty = alpha * (abs(xsf - xf))

    #y_penalty
    y0 = start[1]
    ysf = y0 + (sf/24)*( \
    sin(float(thtsf.subs(s,0))) + 4*sin(float(thtsf.subs(s,sf/8)))  + \
    2*sin(float(thtsf.subs(s,(2*sf)/8))) + 4*sin(float(thtsf.subs(s,(3*sf)/8))) + \
    2*sin(float(thtsf.subs(s,(4*sf)/8))) + 4*sin(float(thtsf.subs(s,(5*sf)/8))) + \
    2*sin(float(thtsf.subs(s,(6*sf)/8))) + 4*sin(float(thtsf.subs(s,(7*sf)/8))) + \
    sin(float(thtsf.subs(s,(8*sf)/8))))

    yf = goal[1]
    y_penalty = alpha * (abs(ysf - yf))

    objective_value = bending_energy + x_penalty + y_penalty + theta_penalty
    print("breakdown:")
    print("total objective_value", objective_value)
    print("bending energy", bending_energy)
    print("x_penalty", x_penalty)
    print("y_penalty", y_penalty)
    print("theta_penalty", theta_penalty)
    return objective_value
Exemple #23
0
    new_locals = {
        sym.name: sympy.Symbol(sym.name, commutative=False)
        for sym in parsed_expr.atoms(sympy.Symbol)
    }

    return sympy.sympify(expr_string, locals=new_locals)


init_session(quiet=True)
init_printing(use_unicode=False,
              wrap_line=False,
              no_global=True,
              use_latex=True)
Nz = 5
dz, bmz, cmz, delta, dt, n, np1, np1ov2, np3ov2, nm1, al, bl, cl, Co, wl, bz, az = sym(
    "Δ_z,b_mz, c_mz,δ, Δ_t,n, n+1, n+1/2, n+3/2, n-1, a_L, b_L, c_L, Co, omega_L, b_z, a_z"
)
# bz, az from cpml update
#al, bl, cl lorentz polarisation
sigmaE, sigmaH, De, K, Kt, Du, Ex, Hy, Je, P, Psi_exy, Psi_hxy = sym(
    "σ_E, σ_H, D_E, K, K^t, D_μ, Ex, Hy, J_e, P, ψ_(exy), ψ_(hxy)",
    commutative=False)

Exnp1 = Ex**np1
Exn = Ex**n
Hypn3ov2 = Hy**np3ov2
Hypn1ov2 = Hy**np1ov2
Pn1 = P**np1
Pn = P**n
Pnm1 = P**nm1
Jen32 = Je**np3ov2
Exemple #24
0
        return f"A {r:0.3f} {r:0.3f} 0 0 {'1' if 0 < self.w else '0'} {p.x:0.3f} {p.y:0.3f}"


if __name__ == '__main__':

    import sympy
    from sympy import symbols as sym

    l1 = Line.from_originPoint_normalVector(Point(4, 1), Vector(4, -2))
    l2 = Line.from_originPoint_normalVector(Point(1, 5), Vector(2, -6))

    print(l1)
    print(l1.debug_canonical())
    print(l2.debug_canonical())

    a1, a2, b1, b2, c1, c2 = sym('a_1 a_2 b_1 b_2 c_1 c_2')
    a1x, a1y, b1x, b1y, a2x, a2y, b2x, b2y = sym(
        'a^1_x a^1_y b^1_x b^1_y a^2_x a^2_y b^2_x b^2_y')

    y = (a2 * c1 - a1 * c2) / (a1 * b2 - a2 * b1)
    print(
        sympy.latex(
            y.subs(a1, a1y).subs(a2, a2y).subs(b1, -a1x).subs(b2, -a2x).subs(
                c1, a1x * b1y - a1y * b1x).subs(c2, a2x * b2y - a2y * b2x)))
    print(l1.intersection_with_line(l2))

    sys.exit(0)

    Arc.from_2_Point(Point(-2, 2), Point(2, 2), 1 / 5)

    line_o = Line.from_2_Point(Point(-1, 0), Point(5, 3))