51 lines
1.4 KiB
Python
51 lines
1.4 KiB
Python
import matplotlib.pyplot as plt
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import numpy as np
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def main():
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directories = {
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"output/relative_error/RK4/",
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"output/relative_error/euler/",
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}
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files = [
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"4000_steps.txt",
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"8000_steps.txt",
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"16000_steps.txt",
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"32000_steps.txt",
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]
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labels = [
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r"4000 steps",
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r"8000 steps",
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r"16000 steps",
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r"32000 steps",
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]
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titles = [
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"Relative error for the RK4 method",
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"Relative error for the forward Euler method"
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]
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fig1, axs1 = plt.subplots(2,1)
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for i, (dir, title) in enumerate(zip(directories, titles)):
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max_err = []
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for label, file in zip(labels, files):
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with open(dir+file) as f:
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lines = f.readlines()
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t = np.linspace(0, 50, len(lines))
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r = np.array([float(line.strip()) for line in lines])
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max_err.append(max(r))
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axs1[i].plot(t, r, label=label)
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axs1[i].set(xlabel=r"t $(\mu s)$", ylabel = r"relative_error $(\mu m)$")
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axs1[i].legend()
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axs1[i].set_title(title)
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conv_rate = 1/3 * sum([np.log10(max_err[i+1]/max_err[i])/np.log10(.5) for i in range(3)])
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print(conv_rate)
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plt.show()
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# fig1.savefig("../latex/images/phase_space_2_particles_x.pdf")
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if __name__ == "__main__":
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main()
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