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diff --git a/buch/papers/laguerre/scripts/rel_error_shifted.py b/buch/papers/laguerre/scripts/rel_error_shifted.py
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+++ b/buch/papers/laguerre/scripts/rel_error_shifted.py
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+if __name__ == "__main__":
+ import matplotlib.pyplot as plt
+ import numpy as np
+ import scipy.special
+
+ import gamma_approx as ga
+
+ n = 8 # order of Laguerre polynomial
+ N = 200 # number of points in interval
+
+ step = 1 / (N - 1)
+ x = np.linspace(step, 1 - step, N + 1)
+ targets = np.arange(10, 14)
+ gamma = scipy.special.gamma(x)
+ fig, ax = plt.subplots(num=1, clear=True, constrained_layout=True, figsize=(5, 2.5))
+ for target in targets:
+ gamma_lag = ga.eval_laguerre_gamma(x, target=target, n=n, func="shifted")
+ rel_error = np.abs(ga.calc_rel_error(gamma, gamma_lag))
+ ax.semilogy(x, rel_error, label=f"$m={target}$", linewidth=3)
+ gamma_lgo = ga.eval_laguerre_gamma(x, n=n, func="optimal_shifted")
+ rel_error = np.abs(ga.calc_rel_error(gamma, gamma_lgo))
+ ax.semilogy(x, rel_error, "m", linestyle="dotted", label="$m^*$", linewidth=3)
+ ax.set_xlim(x[0], x[-1])
+ ax.set_ylim(5e-9, 5e-8)
+ ax.set_xlabel(r"$z$")
+ ax.set_xticks(np.linspace(0, 1, 6))
+ ax.set_xticks(np.linspace(0, 1, 11), minor=True)
+ ax.grid(1, "both")
+ ax.legend(ncol=1, fontsize=ga.fontsize)
+ fig.savefig(f"{ga.img_path}/rel_error_shifted.pgf")
+ # plt.show()