python/pandas_select_columns.ipynb

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  "metadata": {
    "colab": {
      "name": "pandas-select-columns.ipynb",
      "provenance": [],
      "collapsed_sections": []
    },
    "kernelspec": {
      "name": "python3",
      "display_name": "Python 3"
    }
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  "cells": [
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "sBn4_vrWHjCi",
        "colab_type": "text"
      },
      "source": [
        "# **Introduction to Pandas dataframe: Select specific column(s) in a DataFrame**\n",
        "\n",
        "Chanin Nantasenamat\n",
        "\n",
        "[*'Data Professor' YouTube channel*](http://youtube.com/dataprofessor)\n",
        "\n",
        "In this Jupyter notebook, I will be showing you how to select specifc column(s) in a DataFrame.\n",
        "\n",
        "---"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "PBWDV57tHmLf",
        "colab_type": "text"
      },
      "source": [
        "## **Download CSV data**"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "pq6EVr5sHXAq",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 208
        },
        "outputId": "1eea0330-050d-4101-c21b-dce27e09cf01"
      },
      "source": [
        "! wget https://raw.githubusercontent.com/dataprofessor/data/master/delaney_solubility_with_descriptors.csv"
      ],
      "execution_count": 10,
      "outputs": [
        {
          "output_type": "stream",
          "text": [
            "--2020-05-03 17:41:00--  https://raw.githubusercontent.com/dataprofessor/data/master/delaney_solubility_with_descriptors.csv\n",
            "Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 151.101.0.133, 151.101.64.133, 151.101.128.133, ...\n",
            "Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|151.101.0.133|:443... connected.\n",
            "HTTP request sent, awaiting response... 200 OK\n",
            "Length: 57370 (56K) [text/plain]\n",
            "Saving to: ‘delaney_solubility_with_descriptors.csv’\n",
            "\n",
            "\r          delaney_s   0%[                    ]       0  --.-KB/s               \rdelaney_solubility_ 100%[===================>]  56.03K  --.-KB/s    in 0.01s   \n",
            "\n",
            "2020-05-03 17:41:00 (3.82 MB/s) - ‘delaney_solubility_with_descriptors.csv’ saved [57370/57370]\n",
            "\n"
          ],
          "name": "stdout"
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "qJ9j-V_zHwm8",
        "colab_type": "code",
        "colab": {}
      },
      "source": [
        "import pandas as pd"
      ],
      "execution_count": 0,
      "outputs": []
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "D6twMV5THz2r",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 415
        },
        "outputId": "3230bda2-d61e-48f6-f232-0dabecc08908"
      },
      "source": [
        "df = pd.read_csv('delaney_solubility_with_descriptors.csv')\n",
        "df"
      ],
      "execution_count": 12,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/html": [
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              "    }\n",
              "\n",
              "    .dataframe thead th {\n",
              "        text-align: right;\n",
              "    }\n",
              "</style>\n",
              "<table border=\"1\" class=\"dataframe\">\n",
              "  <thead>\n",
              "    <tr style=\"text-align: right;\">\n",
              "      <th></th>\n",
              "      <th>MolLogP</th>\n",
              "      <th>MolWt</th>\n",
              "      <th>NumRotatableBonds</th>\n",
              "      <th>AromaticProportion</th>\n",
              "      <th>logS</th>\n",
              "    </tr>\n",
              "  </thead>\n",
              "  <tbody>\n",
              "    <tr>\n",
              "      <th>0</th>\n",
              "      <td>2.59540</td>\n",
              "      <td>167.850</td>\n",
              "      <td>0.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>-2.180</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1</th>\n",
              "      <td>2.37650</td>\n",
              "      <td>133.405</td>\n",
              "      <td>0.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>-2.000</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>2</th>\n",
              "      <td>2.59380</td>\n",
              "      <td>167.850</td>\n",
              "      <td>1.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>-1.740</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>3</th>\n",
              "      <td>2.02890</td>\n",
              "      <td>133.405</td>\n",
              "      <td>1.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>-1.480</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>4</th>\n",
              "      <td>2.91890</td>\n",
              "      <td>187.375</td>\n",
              "      <td>1.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>-3.040</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>...</th>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1139</th>\n",
              "      <td>1.98820</td>\n",
              "      <td>287.343</td>\n",
              "      <td>8.0</td>\n",
              "      <td>0.000000</td>\n",
              "      <td>1.144</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1140</th>\n",
              "      <td>3.42130</td>\n",
              "      <td>286.114</td>\n",
              "      <td>2.0</td>\n",
              "      <td>0.333333</td>\n",
              "      <td>-4.925</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1141</th>\n",
              "      <td>3.60960</td>\n",
              "      <td>308.333</td>\n",
              "      <td>4.0</td>\n",
              "      <td>0.695652</td>\n",
              "      <td>-3.893</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1142</th>\n",
              "      <td>2.56214</td>\n",
              "      <td>354.815</td>\n",
              "      <td>3.0</td>\n",
              "      <td>0.521739</td>\n",
              "      <td>-3.790</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1143</th>\n",
              "      <td>2.02164</td>\n",
              "      <td>179.219</td>\n",
              "      <td>1.0</td>\n",
              "      <td>0.461538</td>\n",
              "      <td>-2.581</td>\n",
              "    </tr>\n",
              "  </tbody>\n",
              "</table>\n",
              "<p>1144 rows × 5 columns</p>\n",
              "</div>"
            ],
            "text/plain": [
              "      MolLogP    MolWt  NumRotatableBonds  AromaticProportion   logS\n",
              "0     2.59540  167.850                0.0            0.000000 -2.180\n",
              "1     2.37650  133.405                0.0            0.000000 -2.000\n",
              "2     2.59380  167.850                1.0            0.000000 -1.740\n",
              "3     2.02890  133.405                1.0            0.000000 -1.480\n",
              "4     2.91890  187.375                1.0            0.000000 -3.040\n",
              "...       ...      ...                ...                 ...    ...\n",
              "1139  1.98820  287.343                8.0            0.000000  1.144\n",
              "1140  3.42130  286.114                2.0            0.333333 -4.925\n",
              "1141  3.60960  308.333                4.0            0.695652 -3.893\n",
              "1142  2.56214  354.815                3.0            0.521739 -3.790\n",
              "1143  2.02164  179.219                1.0            0.461538 -2.581\n",
              "\n",
              "[1144 rows x 5 columns]"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 12
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "uc36WETtHp77",
        "colab_type": "text"
      },
      "source": [
        "## **Selecting specific column(s)**"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "Ha6n6gH3IsPs",
        "colab_type": "text"
      },
      "source": [
        "### Selecting a single column"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "94xKLaCoHpeY",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 225
        },
        "outputId": "7bc417a4-ff9e-43c4-f05a-7dc4eb5aa387"
      },
      "source": [
        "df.MolLogP"
      ],
      "execution_count": 13,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "0       2.59540\n",
              "1       2.37650\n",
              "2       2.59380\n",
              "3       2.02890\n",
              "4       2.91890\n",
              "         ...   \n",
              "1139    1.98820\n",
              "1140    3.42130\n",
              "1141    3.60960\n",
              "1142    2.56214\n",
              "1143    2.02164\n",
              "Name: MolLogP, Length: 1144, dtype: float64"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 13
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "ua7cZKWzIP-J",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 225
        },
        "outputId": "3cff5ff9-f26a-43ea-9c53-7772d68c48e2"
      },
      "source": [
        "df['MolLogP']"
      ],
      "execution_count": 14,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/plain": [
              "0       2.59540\n",
              "1       2.37650\n",
              "2       2.59380\n",
              "3       2.02890\n",
              "4       2.91890\n",
              "         ...   \n",
              "1139    1.98820\n",
              "1140    3.42130\n",
              "1141    3.60960\n",
              "1142    2.56214\n",
              "1143    2.02164\n",
              "Name: MolLogP, Length: 1144, dtype: float64"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 14
        }
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {
        "id": "Mb_loyXfIyhw",
        "colab_type": "text"
      },
      "source": [
        "### Selecting two or more columns"
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "ZbLCqhFbIRfS",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 415
        },
        "outputId": "d1d61288-290a-4fce-db4b-e3fbf635ba4d"
      },
      "source": [
        "df[['MolLogP','NumRotatableBonds']]"
      ],
      "execution_count": 23,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/html": [
              "<div>\n",
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              "<table border=\"1\" class=\"dataframe\">\n",
              "  <thead>\n",
              "    <tr style=\"text-align: right;\">\n",
              "      <th></th>\n",
              "      <th>MolLogP</th>\n",
              "      <th>NumRotatableBonds</th>\n",
              "    </tr>\n",
              "  </thead>\n",
              "  <tbody>\n",
              "    <tr>\n",
              "      <th>0</th>\n",
              "      <td>2.59540</td>\n",
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              "    </tr>\n",
              "    <tr>\n",
              "      <th>1</th>\n",
              "      <td>2.37650</td>\n",
              "      <td>0.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>2</th>\n",
              "      <td>2.59380</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>3</th>\n",
              "      <td>2.02890</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>4</th>\n",
              "      <td>2.91890</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>...</th>\n",
              "      <td>...</td>\n",
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              "    <tr>\n",
              "      <th>1139</th>\n",
              "      <td>1.98820</td>\n",
              "      <td>8.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1140</th>\n",
              "      <td>3.42130</td>\n",
              "      <td>2.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1141</th>\n",
              "      <td>3.60960</td>\n",
              "      <td>4.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1142</th>\n",
              "      <td>2.56214</td>\n",
              "      <td>3.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1143</th>\n",
              "      <td>2.02164</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "  </tbody>\n",
              "</table>\n",
              "<p>1144 rows × 2 columns</p>\n",
              "</div>"
            ],
            "text/plain": [
              "      MolLogP  NumRotatableBonds\n",
              "0     2.59540                0.0\n",
              "1     2.37650                0.0\n",
              "2     2.59380                1.0\n",
              "3     2.02890                1.0\n",
              "4     2.91890                1.0\n",
              "...       ...                ...\n",
              "1139  1.98820                8.0\n",
              "1140  3.42130                2.0\n",
              "1141  3.60960                4.0\n",
              "1142  2.56214                3.0\n",
              "1143  2.02164                1.0\n",
              "\n",
              "[1144 rows x 2 columns]"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 23
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "qxMA09nEIV7e",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 415
        },
        "outputId": "6f1131df-d3ff-4735-96d5-166a11c03f56"
      },
      "source": [
        "df.iloc[:,[0,2]]"
      ],
      "execution_count": 22,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/html": [
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              "    }\n",
              "\n",
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              "<table border=\"1\" class=\"dataframe\">\n",
              "  <thead>\n",
              "    <tr style=\"text-align: right;\">\n",
              "      <th></th>\n",
              "      <th>MolLogP</th>\n",
              "      <th>NumRotatableBonds</th>\n",
              "    </tr>\n",
              "  </thead>\n",
              "  <tbody>\n",
              "    <tr>\n",
              "      <th>0</th>\n",
              "      <td>2.59540</td>\n",
              "      <td>0.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1</th>\n",
              "      <td>2.37650</td>\n",
              "      <td>0.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>2</th>\n",
              "      <td>2.59380</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>3</th>\n",
              "      <td>2.02890</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>4</th>\n",
              "      <td>2.91890</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>...</th>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1139</th>\n",
              "      <td>1.98820</td>\n",
              "      <td>8.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1140</th>\n",
              "      <td>3.42130</td>\n",
              "      <td>2.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1141</th>\n",
              "      <td>3.60960</td>\n",
              "      <td>4.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1142</th>\n",
              "      <td>2.56214</td>\n",
              "      <td>3.0</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1143</th>\n",
              "      <td>2.02164</td>\n",
              "      <td>1.0</td>\n",
              "    </tr>\n",
              "  </tbody>\n",
              "</table>\n",
              "<p>1144 rows × 2 columns</p>\n",
              "</div>"
            ],
            "text/plain": [
              "      MolLogP  NumRotatableBonds\n",
              "0     2.59540                0.0\n",
              "1     2.37650                0.0\n",
              "2     2.59380                1.0\n",
              "3     2.02890                1.0\n",
              "4     2.91890                1.0\n",
              "...       ...                ...\n",
              "1139  1.98820                8.0\n",
              "1140  3.42130                2.0\n",
              "1141  3.60960                4.0\n",
              "1142  2.56214                3.0\n",
              "1143  2.02164                1.0\n",
              "\n",
              "[1144 rows x 2 columns]"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 22
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "V53KSsZjId1X",
        "colab_type": "code",
        "colab": {
          "base_uri": "https://localhost:8080/",
          "height": 415
        },
        "outputId": "81be4e24-2bac-4dd5-97d7-32ece84768c6"
      },
      "source": [
        "selection = ['MolLogP','NumRotatableBonds', 'logS']\n",
        "df[selection]"
      ],
      "execution_count": 25,
      "outputs": [
        {
          "output_type": "execute_result",
          "data": {
            "text/html": [
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              "\n",
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              "<table border=\"1\" class=\"dataframe\">\n",
              "  <thead>\n",
              "    <tr style=\"text-align: right;\">\n",
              "      <th></th>\n",
              "      <th>MolLogP</th>\n",
              "      <th>NumRotatableBonds</th>\n",
              "      <th>logS</th>\n",
              "    </tr>\n",
              "  </thead>\n",
              "  <tbody>\n",
              "    <tr>\n",
              "      <th>0</th>\n",
              "      <td>2.59540</td>\n",
              "      <td>0.0</td>\n",
              "      <td>-2.180</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1</th>\n",
              "      <td>2.37650</td>\n",
              "      <td>0.0</td>\n",
              "      <td>-2.000</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>2</th>\n",
              "      <td>2.59380</td>\n",
              "      <td>1.0</td>\n",
              "      <td>-1.740</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>3</th>\n",
              "      <td>2.02890</td>\n",
              "      <td>1.0</td>\n",
              "      <td>-1.480</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>4</th>\n",
              "      <td>2.91890</td>\n",
              "      <td>1.0</td>\n",
              "      <td>-3.040</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>...</th>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "      <td>...</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1139</th>\n",
              "      <td>1.98820</td>\n",
              "      <td>8.0</td>\n",
              "      <td>1.144</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1140</th>\n",
              "      <td>3.42130</td>\n",
              "      <td>2.0</td>\n",
              "      <td>-4.925</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1141</th>\n",
              "      <td>3.60960</td>\n",
              "      <td>4.0</td>\n",
              "      <td>-3.893</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1142</th>\n",
              "      <td>2.56214</td>\n",
              "      <td>3.0</td>\n",
              "      <td>-3.790</td>\n",
              "    </tr>\n",
              "    <tr>\n",
              "      <th>1143</th>\n",
              "      <td>2.02164</td>\n",
              "      <td>1.0</td>\n",
              "      <td>-2.581</td>\n",
              "    </tr>\n",
              "  </tbody>\n",
              "</table>\n",
              "<p>1144 rows × 3 columns</p>\n",
              "</div>"
            ],
            "text/plain": [
              "      MolLogP  NumRotatableBonds   logS\n",
              "0     2.59540                0.0 -2.180\n",
              "1     2.37650                0.0 -2.000\n",
              "2     2.59380                1.0 -1.740\n",
              "3     2.02890                1.0 -1.480\n",
              "4     2.91890                1.0 -3.040\n",
              "...       ...                ...    ...\n",
              "1139  1.98820                8.0  1.144\n",
              "1140  3.42130                2.0 -4.925\n",
              "1141  3.60960                4.0 -3.893\n",
              "1142  2.56214                3.0 -3.790\n",
              "1143  2.02164                1.0 -2.581\n",
              "\n",
              "[1144 rows x 3 columns]"
            ]
          },
          "metadata": {
            "tags": []
          },
          "execution_count": 25
        }
      ]
    },
    {
      "cell_type": "code",
      "metadata": {
        "id": "rF85rPt1I9sY",
        "colab_type": "code",
        "colab": {}
      },
      "source": [
        ""
      ],
      "execution_count": 0,
      "outputs": []
    }
  ]
}