1 files changed, 42 insertions, 0 deletions
diff --git a/buch/papers/laguerre/scripts/integrand.py b/buch/papers/laguerre/scripts/integrand.py
new file mode 100644
index 0000000..e970721
--- /dev/null
+++ b/buch/papers/laguerre/scripts/integrand.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+# -*- coding:utf-8 -*-
+"""Plot for integrand of gamma function with shifting terms."""
+
+if __name__ == "__main__":
+    import os
+    from pathlib import Path
+
+    import matplotlib as mpl
+    import matplotlib.pyplot as plt
+    import numpy as np
+
+    mpl.rcParams.update(
+        {
+            "mathtext.fontset": "stix",
+            "font.family": "serif",
+            "font.serif": "TeX Gyre Termes",
+        }
+    )
+    
+    EPSILON = 1e-12
+    xlims = np.array([-3, 3])
+
+    root = str(Path(__file__).parent)
+    img_path = f"{root}/../images"
+    os.makedirs(img_path, exist_ok=True)
+
+    t = np.logspace(*xlims, 1001)[:, None]
+
+    z = np.array([-4.5, -2, -1, -0.5, 0.0, 0.5, 1, 2, 4.5])
+    r = t ** z
+
+    fig, ax = plt.subplots(num=1, clear=True, constrained_layout=True, figsize=(4, 2.4))
+    ax.semilogx(t, r)
+    ax.set_xlim(*(10.0 ** xlims))
+    ax.set_ylim(1e-3, 40)
+    ax.set_xlabel(r"$x$")
+    # ax.set_ylabel(r"$x^z$")
+    ax.grid(1, "both")
+    labels = [f"$z={zi: 3.1f}$" for zi in np.squeeze(z)]
+    ax.legend(labels, ncol=2, loc="upper left", fontsize="small")
+    fig.savefig(f"{img_path}/integrand.pdf")