named-constructors.ipynb

named-constructors.ipynb

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      "authorship_tag": "ABX9TyNM0DTERJ3bULpoyNAiGCs3",
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      "name": "python3",
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    "language_info": {
      "name": "python"
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  "cells": [
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      "cell_type": "markdown",
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        "id": "view-in-github",
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      "source": [
        "<a href=\"https://colab.research.google.com/gist/simecek/fbe0fa354d5771d6fc82c2a3dc80696a/named-constructors.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
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        "id": "VZa0ONOw_dTs",
        "outputId": "88d19998-90e6-4756-80dc-a7a04b0588fd"
      },
      "outputs": [
        {
          "output_type": "stream",
          "name": "stdout",
          "text": [
            "US Letter - Width: 215.89999999999998 mm, Height: 279.4 mm\n",
            "ISO A4 - Width: 297.25 mm, Height: 210.25 mm\n",
            "ISO A5 - Width: 297.25 mm, Height: 105.125 mm\n"
          ]
        }
      ],
      "source": [
        "class PaperSize:\n",
        "    @classmethod\n",
        "    def iso_a4(cls):\n",
        "        return cls.iso_a(4)\n",
        "\n",
        "    @classmethod\n",
        "    def iso_a5(cls):\n",
        "        return cls.iso_a(5)\n",
        "\n",
        "    @classmethod\n",
        "    def iso_a(cls, number):\n",
        "        \"\"\"Construct ISO A series paper sizes.\"\"\"\n",
        "        base_width, base_height = 841, 1189  # Base dimensions for A0 size in mm\n",
        "        if number == 0:\n",
        "            width, height = base_width, base_height\n",
        "        else:\n",
        "            width, height = base_height / (2 ** ((number + 1) // 2)), base_width / (2 ** (number // 2))\n",
        "        return cls(width, height)\n",
        "\n",
        "\n",
        "    @classmethod\n",
        "    def us_letter(cls):\n",
        "        return cls.in_inches(8.5, 11)\n",
        "\n",
        "    @classmethod\n",
        "    def in_inches(cls, width_inch, height_inch):\n",
        "        width_mm = width_inch * 25.4\n",
        "        height_mm = height_inch * 25.4\n",
        "        return cls(width_mm, height_mm)\n",
        "\n",
        "    def __init__(self, width_mm, height_mm):\n",
        "        self.width_mm = width_mm\n",
        "        self.height_mm = height_mm\n",
        "\n",
        "# Creating an instance of PaperSize using the class methods\n",
        "us_letter_paper = PaperSize.us_letter()\n",
        "iso_a4_paper = PaperSize.iso_a4()\n",
        "iso_a5_paper = PaperSize.iso_a5()\n",
        "\n",
        "# Accessing the attributes and printing them\n",
        "print(f\"US Letter - Width: {us_letter_paper.width_mm} mm, Height: {us_letter_paper.height_mm} mm\")\n",
        "print(f\"ISO A4 - Width: {iso_a4_paper.width_mm} mm, Height: {iso_a4_paper.height_mm} mm\")\n",
        "print(f\"ISO A5 - Width: {iso_a5_paper.width_mm} mm, Height: {iso_a5_paper.height_mm} mm\")"
      ]
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}

width, height = base_height / (2 ** (number // 2)), base_width / (2 ** ((number + 1) // 2))

should have the number vs number + 1 swapped around, i.e.,

width, height = base_height / (2 ** ((number + 1) // 2)), base_width / (2 ** (number // 2))