64 lines
1.5 KiB
Python
64 lines
1.5 KiB
Python
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#!/usr/bin/env python3
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import sys
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import os
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import numpy as np
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Nx = int(sys.argv[1])
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Ny = int(sys.argv[2])
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param = sys.argv[3]
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buffer = bytearray(b" "*(3*Nx*Ny))
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Lx = 32 #128 #Physikalische Laenge des Gebietes in x-Richtung
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Ly =32 #128#Physikalische Laenge des Gebietes in y-Richtung
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x, y = np.meshgrid(np.arange(Nx)* Lx/Nx, np.arange(Ny)* Ly/Ny) #x-Array
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kx, ky = np.meshgrid(np.fft.fftfreq(Nx,Lx/(Nx*2.0*np.pi)), np.fft.fftfreq(Ny,Ly/(Ny*2.0*np.pi)))
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ksq = kx*kx + ky*ky
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c = 0.0+(np.random.random((Ny,Nx))-0.5)*0.1
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eps=0.3
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delta=0.0
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#eps = 0.1
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#delta = 1.0
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t = 0.0
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dt = 0.01
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T_End = 300000
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N_t = int(T_End / dt)
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plotEveryNth = 100
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ck = np.fft.fft2(c) #FFT(c)
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# Lineare Terme
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def rhs_lin(ksq):
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result=eps-(1.0-ksq)**2
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return result
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Eu=1.0/(1.0-dt*rhs_lin(ksq))
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i = 0
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def lerp_sat(a, t, b):
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v = (1-t)*a+t*b
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v = int(v)
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if v < 0:
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v = 0
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if v > 255:
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v = 255
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return v
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while True:
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i+= 1
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ck=Eu*(ck+dt*(delta*np.fft.fft2(np.fft.ifft2(ck)**2)-np.fft.fft2(np.fft.ifft2(ck)**3)))
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c=np.fft.ifft2(ck)
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eps = 0.1+0.2*np.cos(i/10000)
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delta = np.sin(i/10000)
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if(i % plotEveryNth == 0):
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myc = c.real
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myc = (myc-np.min(myc))/(np.max(myc)-np.min(myc))
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for px in range(Nx):
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for py in range(Ny):
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idx = 3*(px+Nx*py)
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buffer[idx+0] = lerp_sat(0xff, myc[py,px], 0x00)
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buffer[idx+1] = lerp_sat(0x00, myc[py,px], 0xff)
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buffer[idx+2] = 0
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os.write(1, buffer)
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