File:Height function plotted against singular variety of binomial generating function with example contours of integration plotted.png
Summary
| Description |
English: Graph of height function for different values in the singular variety of . The red dot corresponds to the critical point . The red circles are possible contours of integration for . Reproduction of a graph from Pemantle, Robin; Wilson, Mark C.; Melczer, Stephen (2024). Analytic Combinatorics in Several Variables (PDF) (2nd ed.). Cambridge University Press. pp. 196. |
| Date | |
| Source | Own work |
| Author | Dom walden |
| PNG development | |
| Source code | Python codeimport matplotlib.pyplot as plt
import numpy as np
def height(x, y, r = [1, 1]):
return - r[0] * np.log(abs(x)) - r[1] * np.log(abs(y))
fig, ax = plt.subplots(subplot_kw={'projection': '3d', 'computed_zorder': False})
x = np.arange(-0.5, 1.5, 0.01)
y = np.arange(-1, 1, 0.01)
X, Y = np.meshgrid(x, y)
z = X + 1j*Y
ax.plot_surface(X, Y, height(z, 1 - z), zorder=0)
ax.scatter(0.5, 0, height(1/2, 1/2), color='red')
theta = np.arange(0, 2 * np.pi, 0.01)
r = 1/10
z = r*np.e**(1j*theta)
x = np.real(z)
y = np.imag(z)
ax.plot(x, y, height(z, 1 - z), c='red')
r = 1/5
z = r*np.e**(1j*theta)
x = np.real(z)
y = np.imag(z)
ax.plot(x, y, height(z, 1 - z), c='red')
r = 1/2
z = r*np.e**(1j*theta)
x = np.real(z)
y = np.imag(z)
ax.plot(x, y, height(z, 1 - z), c='red')
ax.set_zlim([0, 3])
fig.set_figwidth(10)
fig.set_figheight(10)
plt.tight_layout()
plt.savefig("height_of_binomial_different_v.png")
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Category:Binomial coefficients
Category:CC-BY-SA-4.0
Category:Complex analysis
Category:Creative Commons Attribution-Share Alike 4.0 missing SDC copyright license
Category:Creative Commons Attribution-Share Alike missing SDC copyright status
Category:PNG created with Matplotlib code
Category:Pages that use a deprecated format of the math tags
Category:Self-published work
Category:Self-published work missing SDC copyright license