Dan Piponi dpiponi

🧱

In material form

Using an IBM Port-a-Punch I wrote my first program in Fortran in around 1978.

dpiponi / defect.py

Created February 20, 2025 19:44

Ising type model using Kawasaki type dynamics

	import taichi as ti
	import taichi.math as tm
	import time
	import random

	ti.init(arch=ti.gpu)

	w = 256
	h = 256
	# pixels = ti.field(dtype=float, shape=(h, w))

dpiponi / gist:ee3d2b74aa5ee1e92032e2c03495ad7c

Created February 22, 2025 16:00

round.py

	import taichi as ti
	import taichi.math as tm
	import time
	import random

	ti.init(arch=ti.gpu)

	w = 1440//2
	h = 1440//2
	# pixels = ti.field(dtype=float, shape=(h, w))

dpiponi / central.py

Created February 22, 2025 19:28

Ising-ish model with central gravitational force

	import taichi as ti
	import taichi.math as tm
	import time
	import random

	ti.init(arch=ti.gpu)

	w = 1440//2
	h = 1440//2
	# pixels = ti.field(dtype=float, shape=(h, w))

dpiponi / caustic.nb

Created March 8, 2025 22:24

Path integral caustics

	length = Compile[{{x, _Real}, {y, _Real}, {\[Theta], _Real}},
	Sin[\[Theta]] +
	Sqrt[(x + Sin[\[Theta]])^2 + (y - Cos[\[Theta]])^2]];
	wavelength = 1/128;
	phaseSum = Compile[
	{{a, _Integer}, {b, _Integer}, {n, _Integer}, {\[Lambda], _Real}, \
	{x, _Real}, {y, _Real}},
	Module[{i = 0, t = 0. + 0. I},
	For[i = a, i <= b, ++i,
	t += \[Pi]/n Exp[I length[x, y, \[Pi]/n i]/\[Lambda]]];

dpiponi / count.cpp

Last active August 25, 2025 21:17

Count number of walks on lattice from (1, 1) to (1, 1) with winding number zero around (1/2, 1/2).

	#include <iostream>

	const long int N = 22;

	long int table[N][1 + 2 * (N + 3) / 4][2 * N + 2][2 * N + 2] = {};

	long int count(long int n, long int w, long int x, long int y)
	{
	long int in = n;
	long int iw = w + 5;