Anonymní profil Elisa – Programujte.com

#4 gna
Moc moc děkuji, to je přesně ono.

#2 gna
Dobře, děkuji. A jak to prosím napravit?

Dobrý den, poradil by mi prosím někdo, jak udělat v dolním obrázku širší šedý přechod (tak aby se podobal hornímu obrázku)? Nastavila jsem dpi na 20, což dá požadovaný tvar, ale lepší přechod je pro větší dpi. Moc děkuji

import matplotlib.pyplot as plt
import numpy as np
from matplotlib.gridspec import GridSpec
import math
fig, ax = plt.subplots()
plt.rcParams["figure.figsize"] = [8, 8]

# Function for plotting parallels to curves
def get_parallels(length=.1):
    
    px, py = [], []
    
    for idx in range(len(x)-1):
        x0, y0, xa, ya = x[idx], y[idx], x[idx+1], y[idx+1]
        dx, dy = xa-x0, ya-y0
        norm = math.hypot(dx, dy) * 1/length
        dx /= norm
        dy /= norm        
        px.append(x0-dy)
        py.append(y0+dx)
    return px, py

def offset(x,y, o):
    """ Offset coordinates given by array x,y by o """
    X = np.c_[x,y].T
    m = np.array([[0,-1],[1,0]])
    R = np.zeros_like(X)
    S = X[:,2:]-X[:,:-2]
    R[:,1:-1] = np.dot(m, S)
    R[:,0] = np.dot(m, X[:,1]-X[:,0])
    R[:,-1] = np.dot(m, X[:,-1]-X[:,-2])
    On = R/np.sqrt(R[0,:]**2+R[1,:]**2)*o
    Out = On+X
    return Out[0,:], Out[1,:]

dpi = 20

def offset_curve(ax, x,y, o):
    """ Offset array x,y in data coordinates
        by o in points """
    trans = ax.transData.transform
    inv = ax.transData.inverted().transform
    X = np.c_[x,y]
    Xt = trans(X)
    xto, yto = offset(Xt[:,0],Xt[:,1],o*dpi/72. )
    Xto = np.c_[xto, yto]
    Xo = inv(Xto)
    return Xo[:,0], Xo[:,1]


fig = plt.figure(constrained_layout=True)

gs = GridSpec(3, 6, figure=fig)
ax5 = fig.add_subplot(gs[1, 3:6])
ax6 = fig.add_subplot(gs[2, :3])
ax7 = fig.add_subplot(gs[2, 3:6])

cmap = plt.get_cmap('Greys_r')

# ax5
x = np.linspace(-1, 1, 100)
y = -x**2
ax5.set_ylim(-1.02, 0.3)
width_l = ax5.get_ylim()[1] - ax5.get_ylim()[0]
for t in np.linspace(0, 1, 40): 
    length =  -0.1*width_l*t
    ax5.plot(*get_parallels(length=length), color=cmap(t/2 + 0.25))

# ax6
x = np.linspace(-3, 3, 100)
y = -(1/4*x**4 - 1.6*x**2) 
ax6.plot(x, y)
ax6.set_xlim(ax6.get_xlim()[0]-0.5, ax6.get_xlim()[1]+0.5)
ax6.scatter(1/2*(ax6.get_xlim()[0] + ax6.get_xlim()[1]), 1.2, marker = 'o', s=900, facecolors='none')
lines = []
width_l = ax6.get_ylim()[1] - ax6.get_ylim()[0]
for t in np.linspace(0, 1, 40):
    l, = ax6.plot(x, y - t * 0.1 * width_l, color=cmap(t/2 + 0.25))
    lines.append(l)

def plot_rainbow(event=None):
    x0 = x
    y0 = y
    for i in range(len(lines)):
        xx, yy = offset_curve(ax, x0, y0, -width_l)
        lines[i].set_data(xx, yy)
        lines[i].set_linewidth(1.1*width_l)
        x0 = xx
        y0 = yy

plot_rainbow()
fig.canvas.mpl_connect("resize_event", plot_rainbow)
fig.canvas.mpl_connect("button_release_event", plot_rainbow)
plt.savefig('fig.pdf')

Připojen obrázek.