在本教程中，我们将学习使用 Python PrettyTable 模块创建一个关系表。我们将在不使用外部库的情况下创建表。
什么是漂亮的桌子？
漂亮的表格是表格形式的数据的可视化表示。这些是 ASCII 表，很容易使用。可修改库由可修改类组成，用于创建关系表。要使用这个库，我们需要使用下面的命令安装它。
装置
pip install prettytable
使用漂亮的表格创建表格
在这里，我们将使用漂亮的表模块创建行方式的表。让我们理解下面的例子。
示例- 1: 逐行创建表格
from prettytable import PrettyTable
# Creating a new table
newTable = PrettyTable(["Student Name", "Class", "Subject", "Makrs"])
# Add rows
newTable.add_row(["Camron", "X", "English", "91"])
newTable.add_row(["Haris", "X", "Math", "63"])
newTable.add_row(["Jenny", "X", "Science", "90"])
newTable.add_row(["Bernald", "X", "Art", "92"])
newTable.add_row(["Jackson", "X", "Science", "98"])
newTable.add_row(["Samual", "X", "English", "88"])
newTable.add_row(["Stark", "X", "English", "95"])
print(newTable)
输出
+--------------+-------+---------+-------+
| Student Name | Class | Subject | Makrs |
+--------------+-------+---------+-------+
| Camron | X | English | 91 |
| Haris | X | Math | 63 |
| Jenny | X | Science | 90 |
| Bernald | X | Art | 92 |
| Jackson | X | Science | 98 |
| Samual | X | English | 88 |
| Stark | X | English | 95 |
+--------------+-------+---------+-------+
示例- 2:列方向表
from prettytable import PrettyTable
columns = ["Student Name", "Class", "Subject", "Marks"]
newTable = PrettyTable()
# Add Columns
newTable.add_column(columns[0], ["Jacob", "Peter", "Grenger",
"Stark", "Falcon", "Matthew", "Jackson"])
newTable.add_column(columns[1], ["X", "X", "X", "X", "X", "X", "X"])
newTable.add_column(columns[2], ["English", "Art", "Science", "Math", "Science", "English", "English"])
newTable.add_column(columns[3], ["91", "63", "90", "92",
"98", "83", "95"])
print(newTable)
输出
+--------------+-------+---------+-------------------+
| Student Name | Class | Subject | Marks |
+--------------+-------+---------+-------------------+
| Jacob | X | English | 91 |
| Peter | X | Art | 63 |
| Grenger | X | Science | 90 |
| Stark | X | Math | 92 |
| Falcon | X | Science | 98 |
| Matthew | X | English | 83 |
| Jackson | X | English | 95 |
+--------------+-------+---------+------------------+
我们使用了漂亮表模块的 add_column() 方法。
示例- 2:一次性添加行
from prettytable import PrettyTable
# Creating a new table
newTable = PrettyTable(["Student Name", "Class", "Subject", "Makrs"])
# # Add rows
newTable.add_rows(
[
["Camron", "X", "English", "91"],
["Haris", "X", "Math", "63"],
["Jenny", "X", "Science", "90"],
["Bernald", "X", "Art", "92"],
["Jackson", "X", "Science", "98"],
["Samual", "X", "English", "88"],
["Stark", "X", "English", "95"],
]
)
print(newTable)
输出
+--------------+-------+---------+-------+
| Camron | X | English | 91 |
| Haris | X | Math | 63 |
| Jenny | X | Science | 90 |
| Bernald | X | Art | 92 |
| Jackson | X | Science | 98 |
| Samual | X | English | 88 |
| Stark | X | English | 95 |
+--------------+-------+---------+-------+
可修改的删除行
这个模块提供了 del_row()方法，允许我们移除行。它接受要删除的索引值并移除行。索引从零开始。让我们理解下面的代码。
示例-
from prettytable import PrettyTable
# Creating a new table
newTable = PrettyTable(["Student Name", "Class", "Subject", "Makrs"])
# # Add rows
newTable.add_row(["Camron", "X", "English", "91"])
newTable.add_row(["Haris", "X", "Math", "63"])
newTable.add_row(["Jenny", "X", "Science", "90"])
newTable.add_row(["Bernald", "X", "Art", "92"])
newTable.add_row(["Jackson", "X", "Science", "98"])
newTable.add_row(["Samual", "X", "English", "88"])
newTable.add_row(["Stark", "X", "English", "95"])
newTable.del_row(1)
newTable.del_row(2)
newTable.del_row(3)
print(newTable)
输出
+--------------+-------+---------+-------+
| Student Name | Class | Subject | Makrs |
+--------------+-------+---------+-------+
| Camron | X | English | 91 |
| Jenny | X | Science | 90 |
| Jackson | X | Science | 98 |
| Stark | X | English | 95 |
+--------------+-------+---------+-------+
它将从表中删除特定的行。要清除整个表，我们使用以下方法。
myTable.clear_rows()
示例- 2
from prettytable import PrettyTable
# Creating a new table
newTable = PrettyTable(["Student Name", "Class", "Subject", "Makrs"])
# # Add rows
newTable.add_row(["Camron", "X", "English", "91"])
newTable.add_row(["Haris", "X", "Math", "63"])
newTable.add_row(["Jenny", "X", "Science", "90"])
newTable.add_row(["Bernald", "X", "Art", "92"])
newTable.add_row(["Jackson", "X", "Science", "98"])
newTable.add_row(["Samual", "X", "English", "88"])
newTable.add_row(["Stark", "X", "English", "95"])
newTable.clear_rows()
print(newTable)
输出
+--------------+-------+---------+------------------+
| Student Name | Class | Subject | Makrs |
+--------------+-------+---------+--------------------+
+--------------+-------+---------+--------------------+
正如我们在上面的代码中看到的，所有的行都被删除了。我们只能看到列名。
获取特定的行和列
可修改的主要目的是得到 ASCII 形式的表格。我们可以使用以下方法来限制表的输出。
get_string(fields=["Column 1", "Column2", .............., ColumnN]
让我们理解下面的例子。
示例:
from prettytable import PrettyTable
# Creating a new table
newTable = PrettyTable(["Student Name", "Class", "Subject", "Makrs"])
# # Add rows
newTable.add_rows(
[
["Camron", "X", "English", "91"],
["Haris", "X", "Math", "63"],
["Jenny", "X", "Science", "90"],
["Bernald", "X", "Art", "92"],
["Jackson", "X", "Science", "98"],
["Samual", "X", "English", "88"],
["Stark", "X", "English", "95"],
]
)
print(newTable.get_string(fields=["Student Name", "Class"]))
输出
+--------------+--------------+
| Student Name | Class |
+--------------+--------------+
| Camron | X |
| Haris | X |
| Jenny | X |
| Bernald | X |
| Jackson | X |
| Samual | X |
| Stark | X |
+--------------+---------------+
field 参数接受要打印的字段名列表。
我们也可以用下面的方法来控制结果。
print(newTable.get_string(start=1, end=4)
输出
+--------------+-------+---------+-------------------+
| Student Name | Class | Subject | Makrs |
+--------------+-------+---------+-------------------+
| Camron | X | English | 91 |
| Haris | X | Math | 63 |
| Jenny | X | Science | 90 |
+--------------+-------+---------+------------------+
更改列的对齐方式
我们可以观察到表中的所有列都居中对齐。我们可以根据需要改变，给分配一个字符，对齐属性。有三个字符串——“l”(代表左边)、“r”(代表右边)和“c”(代表中间)分别对齐。
让我们看看下面的例子。
示例-
newTable.align = 'r'
print(newTable)
输出
+--------------+-------+---------+-------------------+
| Student Name | Class | Subject | Makrs |
+--------------+-------+---------+------------------+
| Camron | X | English | 91 |
| Haris | X | Math | 63 |
| Jenny | X | Science | 90 |
| Bernald | X | Art | 92 |
| Jackson | X | Science | 98 |
| Samual | X | English | 88 |
| Stark | X | English | 95 |
+--------------+-------+---------+------------------+
更改表格的外观
默认表看起来像一个 SQL 数据库 Shell。但是，我们可以用其他格式修改表格外观。漂亮的表格模块提供了 set_style() 方法，在 MSWord 友好中转换表格。
让我们看看下面的例子。
示例-在创建表代码中添加以下代码。
from prettytable import MSWORD_FRIENDLY
newTable.set_style(MSWORD_FRIENDLY)
print(newTable)
输出
| Student Name | Class | Subject | Makrs |
| Camron | X | English | 91 |
| Haris | X | Math | 63 |
| Jenny | X | Science | 90 |
| Bernald | X | Art | 92 |
| Jackson | X | Science | 98 |
| Samual | X | English | 88 |
| Stark | X | English | 95 |
我们可以清楚地看到默认表和 MSWord 友好表的区别。
结论
我们已经使用可修改的模块讨论了表格中的一些重要操作。这是一个使用 Python 脚本处理表的非常有效的模块。
