{
  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "\n# SGD: Maximum margin separating hyperplane\n\nPlot the maximum margin separating hyperplane within a two-class\nseparable dataset using a linear Support Vector Machines classifier\ntrained using SGD.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "# Authors: The scikit-learn developers\n# SPDX-License-Identifier: BSD-3-Clause\n\nimport matplotlib.pyplot as plt\nimport numpy as np\n\nfrom sklearn.datasets import make_blobs\nfrom sklearn.linear_model import SGDClassifier\n\n# we create 50 separable points\nX, Y = make_blobs(n_samples=50, centers=2, random_state=0, cluster_std=0.60)\n\n# fit the model\nclf = SGDClassifier(loss=\"hinge\", alpha=0.01, max_iter=200)\n\nclf.fit(X, Y)\n\n# plot the line, the points, and the nearest vectors to the plane\nxx = np.linspace(-1, 5, 10)\nyy = np.linspace(-1, 5, 10)\n\nX1, X2 = np.meshgrid(xx, yy)\nZ = np.empty(X1.shape)\nfor (i, j), val in np.ndenumerate(X1):\n    x1 = val\n    x2 = X2[i, j]\n    p = clf.decision_function([[x1, x2]])\n    Z[i, j] = p[0]\nlevels = [-1.0, 0.0, 1.0]\nlinestyles = [\"dashed\", \"solid\", \"dashed\"]\ncolors = \"k\"\nplt.contour(X1, X2, Z, levels, colors=colors, linestyles=linestyles)\nplt.scatter(X[:, 0], X[:, 1], c=Y, cmap=plt.cm.Paired, edgecolor=\"black\", s=20)\n\nplt.axis(\"tight\")\nplt.show()"
      ]
    }
  ],
  "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": "3.9.21"
    }
  },
  "nbformat": 4,
  "nbformat_minor": 0
}