python - modelling crowd movement with matplotlib -

-

i model basic crowd movement python. want show animation. have made following program test matplotlib :

import numpy np import matplotlib.pyplot plt matplotlib import animation  #size of crowd n = 100  def gen_data():     """ init position , speed of each people """     x = y = np.zeros(n)     theta = np.random.random(n) * 360 / (2 * np.pi)     v0 = 0.1     vx, vy = v0 * np.cos(theta), v0 * np.sin(theta)     return np.array([x, y, vx, vy]).t  def init():     line in lines:         line.set_data([],[])     return line,  def update_lines(i, lines, data):     d, line in zip(data, lines):         d[0:2] += d[2:4]         if abs(d[0]) > 5: d[2] *= -1         if abs(d[1]) > 5: d[3] *= -1         line.set_data(d[0] ,d[1])     return lines  fig = plt.figure() ax = plt.axes(xlim=(-5,5),ylim=(-5,5)) lines = [plt.plot([],[], 'ko')[0] in range(n)]  data = gen_data()  anim = animation.funcanimation(fig, update_lines, init_func=init, fargs=(lines, data), interval=10, blit=true)  plt.show()

even n=100, animation slow... there can speed mathplotlib ? matplotlib best graphic tool make thins kind of animation python ? if no, ?

here 3 things can make animation faster:

  • replace n calls plt.plot one call plt.scatter.

  • replace for-loop in update assignments modify whole slices of data @ once:

    data[:, 0:2] += data[:, 2:4] data[:, 2] = np.where(np.abs(data[:, 0]) > 5, -data[:, 2], data[:, 2]) data[:, 3] = np.where(np.abs(data[:, 1]) > 5, -data[:, 3], data[:, 3])

  • reduce interval=10 interval=0. 

import numpy np import matplotlib.pyplot plt matplotlib import animation  # size of crowd n = 100  def gen_data():     """ init position , speed of each people """     x = y = np.zeros(n)     theta = np.random.random(n) * 360 / (2 * np.pi)     v0 = 0.1     vx, vy = v0 * np.cos(theta), v0 * np.sin(theta)     return np.column_stack([x, y, vx, vy])  def init():     pathcol.set_offsets([[], []])     return pathcol,  def update(i, pathcol, data):     data[:, 0:2] += data[:, 2:4]     data[:, 2] = np.where(np.abs(data[:, 0]) > 5, -data[:, 2], data[:, 2])     data[:, 3] = np.where(np.abs(data[:, 1]) > 5, -data[:, 3], data[:, 3])     pathcol.set_offsets(data[:, 0:2])     return [pathcol]  fig = plt.figure() ax = plt.axes(xlim=(-5, 5), ylim=(-5, 5)) pathcol = plt.scatter([], []) data = gen_data() anim = animation.funcanimation(fig, update, init_func=init,                                fargs=(pathcol, data), interval=0, blit=true) plt.show()

Comments

Post a Comment

Popular posts from this blog

python - No exponential form of the z-axis in matplotlib-3D-plots -

-
Image
i have similar problem described in how prevent numbers being changed exponential form in python matplotlib figure : i don't want (in special case) weird scientific formatting of axis. problem different have problem @ z -axis. 2-d plots can use ax.get_yaxis().get_major_formatter().set_useoffset(false) . , there no function ax.get_zaxis() what use format z -axis same way? edit: example: from mpl_toolkits.mplot3d import axes3d import numpy np import sys import matplotlib import matplotlib.pyplot pyplot def func(xi, ti): res = 10e3 + np.cos(ti) * np.sin(xi) return res if __name__ == '__main__': timespacing = 20 timestart = 0 timeend = 1 time = np.linspace(timestart, timeend, timespacing) widthspacing = 50 widthstart = 0 widthend = 3 width = np.linspace(widthstart, widthend, widthspacing) reslist = [] matplotlib.rcparams['legend.fontsize'] = 10 fig = pyplot.figure() ax = fig.gca(projection = '3d...
Read more

php - Best Light server (Linux + Web server + Database) for Raspberry Pi -

-
i install web server database on raspberry pi (little computer). computer has 1gb ram. i want know best combination: linux distribution , web server , dbms run local server multiple users minimal latency, use php on server. , best settings performance , not have bugs (memory usage, disable plugin, disable service, etc)? i thought light debian , lighttpd server , sqlite database. solution? i think lighttpd + sqlite great choice. linux distro, debian @ centos or tiny core linux , although i'm not sure of compatibility pi. obviously, can't go wrong raspbian if want use in production , more stable performance, few more pi's , set them in cluster .
Read more

c# - "Newtonsoft.Json.JsonSerializationException unable to find constructor to use for types" error when deserializing class -

-
i developing app in xamarin android. have splash screen serialize class , pass mainactivity using intent . when try deserialize in mainactivity error message : "serializationexception unable find constructor use types" serialization : void loaddata() { currency currency = new currency(this); intent = new intent(this, typeof(mainactivity)); intent.putextra("currency", newtonsoft.json.jsonconvert.serializeobject(currency)); startactivity(intent); } deserialization : cur = newtonsoft.json.jsonconvert.deserializeobject<currency> (intent.getstringextra("currency")); // error here class constructor : public currency(context context) { thiscontext = context; } i began experiencing problem after added parameter context context constructor. has caused this? how can solve it? possible serialize/deserialize class has parameters? you need have empty constructor in currency class in order deserialize it. ...
Read more