{
  "cells": [
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "# This file is part of nannos\n# License: GPLv3\n%matplotlib inline"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "\n# Tangent field\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "import importlib\nimport time\n\nimport matplotlib.pyplot as plt\n\nimport nannos as nn\nfrom nannos.formulations.tangent import get_tangent_field\n\nbk = nn.backend\nplt.close(\"all\")\n# plt.ion()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "We will generate a field tangent to the material interface\n\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "scale = 1.5\nnh = 600\nlattice = nn.Lattice(([1 * scale, 0], [0, scale]), discretization=2**9)\n\nx, y = lattice.grid\ncirc = lattice.ellipse(\n    (0.3 * scale, 0.3 * scale), (0.1 * scale, 0.25 * scale), rotate=-30\n)\nrect = lattice.rectangle(\n    (0.7 * scale, 0.7 * scale), (0.2 * scale, 0.5 * scale), rotate=20\n)\ngrid = lattice.ones() * (3 + 0.01j)\ngrid[circ] = 1\ngrid[rect] = 1\n\nst = lattice.Layer(\"pat\", thickness=scale, epsilon=grid)\nlays = [lattice.Layer(\"sup\"), st, lattice.Layer(\"sub\")]\npw = nn.PlaneWave(wavelength=1 / 1.2)\nsim = nn.Simulation(lays, pw, nh)"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "FFT version\n\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "rfilt = 2\ndsp = 10\nt0 = -time.time()\nt = get_tangent_field(\n    lattice, grid, sim.harmonics, normalize=False, type=\"fft\", rfilt=rfilt\n)\nt0 += time.time()\nprint(f\"Elapsed time {t0:.4f}s\")\n\n\nplt.figure()\nst.plot()\nplt.quiver(\n    x[::dsp, ::dsp],\n    y[::dsp, ::dsp],\n    t[0][::dsp, ::dsp],\n    t[1][::dsp, ::dsp],\n    scale=11,\n)\nplt.axis(\"scaled\")\n_ = plt.axis(\"off\")\nplt.show()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "FFT version (normalized)\n\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "t0 = -time.time()\ntnorma = get_tangent_field(\n    lattice, grid, sim.harmonics, normalize=True, type=\"fft\", rfilt=rfilt\n)\nt0 += time.time()\nprint(f\"Elapsed time {t0:.4f}s\")\n\n\nplt.figure()\nst.plot()\nplt.quiver(\n    x[::dsp, ::dsp],\n    y[::dsp, ::dsp],\n    tnorma[0][::dsp, ::dsp],\n    tnorma[1][::dsp, ::dsp],\n    scale=50,\n)\nplt.axis(\"scaled\")\n_ = plt.axis(\"off\")\nplt.show()"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "import nannos.utils.jupyter\n%nannos_version_table"
      ]
    }
  ],
  "metadata": {
    "kernelspec": {
      "display_name": "Python 3",
      "language": "python",
      "name": "python3"
    },
    "language_info": {
      "codemirror_mode": {
        "name": "ipython",
        "version": 3
      },
      "file_extension": ".py",
      "mimetype": "text/x-python",
      "name": "python",
      "nbconvert_exporter": "python",
      "pygments_lexer": "ipython3",
      "version": "3.14.3"
    }
  },
  "nbformat": 4,
  "nbformat_minor": 0
}