我正在编写一个小型可视化项目,它假设在几个带电体周围显示矢量场。
我的问题是下一个: 从主要位置移动圆(带电粒子)后,我不知道如何更新箭袋场。
链接到图片,因为我的声誉太低了。我几乎是stackoverflow的新手。
from pylab import *
from scipy import *
import matplotlib.pyplot as plt
import matplotlib.patches as patches
import scipy.constants as const
skr = const.pi*const.epsilon_0*4
class DraggablePoint:
def __init__(self, p, q0):
self.q = q0
self.point = p
self.c_kruznice = p.center
self.press = None
def connect(self):
self.cidpress = self.point.figure.canvas.mpl_connect('button_press_event', self.button_press_event)
self.cidrelease = self.point.figure.canvas.mpl_connect('button_release_event',self.button_release_event)
self.cidmotion = self.point.figure.canvas.mpl_connect('motion_notify_event', self.motion_notify_event)
def disconnect(self):
self.point.figure.canvas.mpl_disconnect(self.cidpress)
self.point.figure.canvas.mpl_disconnect(self.cidrelease)
self.point.figure.canvas.mpl_disconnect(self.cidmotion)
def button_press_event(self,event):
if event.inaxes != self.point.axes:
return
contains = self.point.contains(event)[0]
if not contains: return
self.press = self.point.center, event.xdata, event.ydata
def button_release_event(self,event):
self.press = None
self.point.figure.canvas.draw()
def motion_notify_event(self, event):
if self.press is None: return
if event.inaxes != self.point.axes: return
self.point.center, xpress, ypress = self.press
dx = event.xdata - xpress
dy = event.ydata - ypress
self.point.center = (self.point.center[0]+dx, self.point.center[1]+dy)
print(self.point.center)
self.point.figure.canvas.draw()
if __name__ == '__main__':
f_s=0.3
def R(x,y):
r=np.sqrt(x**2+y**2)+f_s
return r
def polje(tela, X, Y):
Ex = 0
Ey = 0
for i in range(len(tela)):
r=R(tela[i].c_kruznice[0] - X, tela[i].c_kruznice[1] - Y )
ex = X - tela[i].c_kruznice[0]
ey = Y - tela[i].c_kruznice[1]
Ex += (tela[i].q/skr)*(1/(r+f_s)**3)*ex
Ey += (tela[i].q/skr)*(1/(r+f_s)**3)*ey
return Ex, Ey
fig = plt.figure(figsize=(8,8))
ax = fig.add_axes([0.05,0.05,0.92,0.92])
ax.set_xlim(-6,6)
ax.set_ylim(-6,6)
scale = 0.2
X,Y=np.mgrid[-5:5:scale, -5:5:scale]
circles = []
q=3*const.e
s=abs(q)
sx=sqrt(s/np.pi)*1e8*5
circle2 = patches.Circle((3,0.3), 0.3, fc='r', alpha=0.5, picker=True)
circle1 = patches.Circle((0.7,0.3), 0.3, fc='r', alpha=0.5, picker=True)
circle = patches.Circle((-4,0.3), 0.3, fc='b', alpha=0.5, picker=True)
circles.append(ax.add_patch(circle1))
circles.append(ax.add_patch(circle))
circles.append(ax.add_patch(circle2))
drs = []
for c in circles:
print(c.center[0])
dr = DraggablePoint(c,-1)
dr.connect()
drs.append(dr)
racun=polje(drs, X, Y)
ax.quiver(X,Y,racun[0],racun[1], color='r', alpha=0.5)
ax.quiver(X,Y,racun[0],racun[1], edgecolor='k', facecolor='None', linewidth =.5)
plt.show ()
答案 0 :(得分:0)
我也是新来的,所以我会尽力帮助。
对我而言合乎逻辑的解决方案是为您的圈子提供索引。每当你移动一个圆圈时,你的班级就会像你一样调用函数button_release_event
。所以,当谈到最后一个圆圈(你给它的特定指数)时,你只需要删除你的情节,然后重新做一遍(你需要画圆圈和场地)。
有趣的是,当它检查圈子时,它将始终在第一个上完成,索引为0.我不确定为什么会发生这种情况,但它很棒,因为它与图表上的圈数无关
此外,您需要拥有行self.c_kruznice = self.point.center[0], self.point.center[1]
,因为它会更新您拖动的点的中心,以便它可以计算字段。关键部分:使用plt.draw()
绘制字段,因为只有在拖动圆圈后才更新字段。因为plt.show()
等待你完成绘制它的所有内容(这就是你开始下一次拖动时绘制的原因),但plt.draw()
在发布时就这样做了。
编辑:您需要在重新绘制之前清除列表circles
(我编辑了代码)。
以下是有这个想法的代码。
from pylab import *
from scipy import *
import matplotlib.pyplot as plt
import matplotlib.patches as patches
import scipy.constants as const
skr = const.pi*const.epsilon_0*4
class DraggablePoint:
global Polje
def __init__(self, p, q0, ind):
self.q = q0
self.point = p
self.c_kruznice = p.center
self.press = None
self.indeks = ind
def connect(self):
self.cidpress = self.point.figure.canvas.mpl_connect('button_press_event', self.button_press_event)
self.cidrelease = self.point.figure.canvas.mpl_connect('button_release_event',self.button_release_event)
self.cidmotion = self.point.figure.canvas.mpl_connect('motion_notify_event', self.motion_notify_event)
def disconnect(self):
self.point.figure.canvas.mpl_disconnect(self.cidpress)
self.point.figure.canvas.mpl_disconnect(self.cidrelease)
self.point.figure.canvas.mpl_disconnect(self.cidmotion)
def button_press_event(self,event):
if event.inaxes != self.point.axes:
return
contains = self.point.contains(event)[0]
if not contains: return
self.press = self.point.center, event.xdata, event.ydata
def button_release_event(self,event):
self.press = None
self.point.figure.canvas.draw()
# This is the part which will erase field
# and draw for us new one
self.c_kruznice = self.point.center[0], self.point.center[1]
if self.indeks == 0:
racun = polje(drs, X, Y)
ax.cla()
circles = []
circles.append(ax.add_patch(circle1))
circles.append(ax.add_patch(circle))
circles.append(ax.add_patch(circle2))
circles.append(ax.add_patch(circle3))
ax.quiver(X,Y,racun[0],racun[1], color='r', alpha=0.5)
ax.quiver(X,Y,racun[0],racun[1], edgecolor='k', facecolor='None', linewidth =.5)
plt.draw()
def motion_notify_event(self, event):
if self.press is None: return
if event.inaxes != self.point.axes: returnO
self.point.center, xpress, ypress = self.press
dx = event.xdata - xpress
dy = event.ydata - ypress
self.point.center = (self.point.center[0]+dx, self.point.center[1]+dy)
self.point.figure.canvas.draw()
if __name__ == '__main__':
f_s=0.3
def R(x,y):
r=np.sqrt(x**2+y**2)+f_s
return r
def polje(tela, X, Y):
Ex = 0
Ey = 0
for i in range(len(tela)):
r = R(tela[i].c_kruznice[0] - X, tela[i].c_kruznice[1] - Y )
ex = X - tela[i].c_kruznice[0]
ey = Y - tela[i].c_kruznice[1]
Ex += (tela[i].q/skr)*(1/(r+f_s)**3)*ex
Ey += (tela[i].q/skr)*(1/(r+f_s)**3)*ey
return Ex, Ey
fig = plt.figure(figsize=(8,8))
ax = fig.add_axes([0.05,0.05,0.92,0.92])
ax.set_xlim(-6,6)
ax.set_ylim(-6,6)
scale = 0.2
X,Y=np.mgrid[-5:5:scale, -5:5:scale]
circles = []
q=3*const.e
s=abs(q)
sx=sqrt(s/np.pi)*1e8*5
circle2 = patches.Circle((2,3), 0.3, fc='r', alpha=0.5, picker=True)
circle1 = patches.Circle((2,-3), 0.3, fc='r', alpha=0.5, picker=True)
circle = patches.Circle((-2,3), 0.3, fc='b', alpha=0.5, picker=True)
circle3 = patches.Circle((-2,-3), 0.3, fc = 'b', alpha = 0.5, picker = True )
circles.append(ax.add_patch(circle1))
circles.append(ax.add_patch(circle))
circles.append(ax.add_patch(circle2))
circles.append(ax.add_patch(circle3))
drs = []
i = 0
q = [-1, 1, -1, 1]
for c in circles:
dr = DraggablePoint(c, q[i], i)
dr.connect()
drs.append(dr)
i += 1
racun = polje(drs, X, Y)
ax.quiver(X,Y,racun[0],racun[1], color='r', alpha=0.5)
ax.quiver(X,Y,racun[0],racun[1], edgecolor='k', facecolor='None', linewidth =.5)
plt.show()