python實用庫：PrettyTable 學習
PrettyTable說明
PrettyTable 是python中的一個第三方庫，可用來生成美觀的ASCII格式的表格，十分實用。
以下為官方介紹：
A simple Python library for easily displaying tabular data in a visually appealing ASCII table format.
PrettyTable is a simple Python library designed to make it quick and easy to represent tabular data in visually appealing ASCII tables. It was inspired by the ASCII tables used in the PostgreSQL shell psql. PrettyTable allows for selection of which columns are to be printed, independent alignment of columns (left or right justified or centred) and printing of “sub-tables” by specifying a row range.
PrettyTable安裝
使用pip即可十分方便的安裝PrettyTable，如下：
pip install PrettyTable
PrettyTable使用示例
github上有PrettyTable的使用說明，鏈接如下：https://github.com/dprince/python-prettytable
以下是具體的使用示例：
import prettytable as pt
## 按行添加數據
tb = pt.PrettyTable()
tb.field_names = ["City name", "Area", "Population", "Annual Rainfall"]
tb.add_row(["Adelaide",1295, 1158259, 600.5])
tb.add_row(["Brisbane",5905, 1857594, 1146.4])
tb.add_row(["Darwin", 112, 120900, 1714.7])
tb.add_row(["Hobart", 1357, 205556,619.5])
print(tb)
+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.5 |
| Brisbane | 5905 | 1857594 | 1146.4 |
| Darwin | 112 | 120900 | 1714.7 |
| Hobart | 1357 | 205556 | 619.5 |
+-----------+------+------------+-----------------+
## 按列添加數據
tb.add_column('index',[1,2,3,4])
print(tb)
+-----------+------+------------+-----------------+-------+
| City name | Area | Population | Annual Rainfall | index |
+-----------+------+------------+-----------------+-------+
| Adelaide | 1295 | 1158259 | 600.5 | 1 |
| Brisbane | 5905 | 1857594 | 1146.4 | 2 |
| Darwin | 112 | 120900 | 1714.7 | 3 |
| Hobart | 1357 | 205556 | 619.5 | 4 |
+-----------+------+------------+-----------------+-------+
## 使用不同的輸出風格
tb.set_style(pt.MSWORD_FRIENDLY)
print('--- style：MSWORD_FRIENDLY -----')
print(tb)
tb.set_style(pt.PLAIN_COLUMNS)
print('--- style：PLAIN_COLUMNS -----')
print(tb)
## 隨機風格，每次不同
tb.set_style(pt.RANDOM)
print('--- style：MSWORD_FRIENDLY -----')
print(tb)
tb.set_style(pt.DEFAULT)
print('--- style：DEFAULT -----')
print(tb)
--- style：MSWORD_FRIENDLY -----
| City name | Area | Population | Annual Rainfall |
| Adelaide | 1295 | 1158259 | 600.5 |
| Brisbane | 5905 | 1857594 | 1146.4 |
| Darwin | 112 | 120900 | 1714.7 |
| Hobart | 1357 | 205556 | 619.5 |
--- style：PLAIN_COLUMNS -----
City name Area Population Annual Rainfall
Adelaide 1295 1158259 600.5
Brisbane 5905 1857594 1146.4
Darwin 112 120900 1714.7
Hobart 1357 205556 619.5
--- style：MSWORD_FRIENDLY -----
@ Adelaide 1295 1158259 600.5 @
@ Brisbane 5905 1857594 1146.4@
@ Darwin 112 120900 1714.7@
@ Hobart 1357 205556 619.5 @
--- style：DEFAULT -----
+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.5 |
| Brisbane | 5905 | 1857594 | 1146.4 |
| Darwin | 112 | 120900 | 1714.7 |
| Hobart | 1357 | 205556 | 619.5 |
+-----------+------+------------+-----------------+
## 不打印，獲取表格字符串
s = tb.get_string()
print(s)
## 可以只獲取指定列或行
s = tb.get_string(fields=["City name", "Population"],start=1,end=4)
print(s)
+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.5 |
| Brisbane | 5905 | 1857594 | 1146.4 |
| Darwin | 112 | 120900 | 1714.7 |
| Hobart | 1357 | 205556 | 619.5 |
+-----------+------+------------+-----------------+
+-----------+------------+
| City name | Population |
+-----------+------------+
| Brisbane | 1857594 |
| Darwin | 120900 |
| Hobart | 205556 |
+-----------+------------+
## 自定義表格輸出樣式
### 設定左對齊
tb.align = 'l'
### 設定數字輸出格式
tb.float_format = "2.2"
### 設定邊框連接符為'*"
tb.junction_char = "*"
### 設定排序方式
tb.sortby = "City name"
### 設定左側不填充空白字符
tb.left_padding_width = 0
print(tb)
*----------*-----*-----------*----------------*
|City name |Area |Population |Annual Rainfall |
*----------*-----*-----------*----------------*
|Adelaide |1295 |1158259 |600.50 |
|Brisbane |5905 |1857594 |1146.40 |
|Darwin |112 |120900 |1714.70 |
|Hobart |1357 |205556 |619.50 |
*----------*-----*-----------*----------------*
## 不顯示邊框
tb.border = 0
print(tb)
## 修改邊框分隔符
tb.set_style(pt.DEFAULT)
tb.horizontal_char = '+'
print(tb)
City name Area Population Annual Rainfall
Adelaide 1295 1158259 600.50
Brisbane 5905 1857594 1146.40
Darwin 112 120900 1714.70
Hobart 1357 205556 619.50
+++++++++++++++++++++++++++++++++++++++++++++++++++
| City name | Area | Population | Annual Rainfall |
+++++++++++++++++++++++++++++++++++++++++++++++++++
| Adelaide | 1295 | 1158259 | 600.50 |
| Brisbane | 5905 | 1857594 | 1146.40 |
| Darwin | 112 | 120900 | 1714.70 |
| Hobart | 1357 | 205556 | 619.50 |
+++++++++++++++++++++++++++++++++++++++++++++++++++
## prettytable也支持輸出HTML代碼
s = tb.get_html_string()
print(s)
<table>
<tr>
<th>City name</th>
<th>Area</th>
<th>Population</th>
<th>Annual Rainfall</th>
</tr>
<tr>
<td>Adelaide</td>
<td>1295</td>
<td>1158259</td>
<td>600.50</td>
</tr>
<tr>
<td>Brisbane</td>
<td>5905</td>
<td>1857594</td>
<td>1146.40</td>
</tr>
<tr>
<td>Darwin</td>
<td>112</td>
<td>120900</td>
<td>1714.70</td>
</tr>
<tr>
<td>Hobart</td>
<td>1357</td>
<td>205556</td>
<td>619.50</td>
</tr>
</table>
## 使用copy方法復制對象
#tb.set_style(pt.DEFAULT)
tb.horizontal_char = '.'
tb2 = tb.copy()
tb.align = 'l'
tb2.align = 'r'
print(tb)
print(tb2)
## 直接賦值，得到的是索引
tb.horizontal_char = '-'
tb.aliign = 'l'
tb3 = tb
tb3.align = 'r'
print(tb)
print(tb3)
+...........+......+............+.................+
| City name | Area | Population | Annual Rainfall |
+...........+......+............+.................+
| Adelaide | 1295 | 1158259 | 600.50 |
| Brisbane | 5905 | 1857594 | 1146.40 |
| Darwin | 112 | 120900 | 1714.70 |
| Hobart | 1357 | 205556 | 619.50 |
+...........+......+............+.................+
+...........+......+............+.................+
| City name | Area | Population | Annual Rainfall |
+...........+......+............+.................+
| Adelaide | 1295 | 1158259 | 600.50 |
| Brisbane | 5905 | 1857594 | 1146.40 |
| Darwin | 112 | 120900 | 1714.70 |
| Hobart | 1357 | 205556 | 619.50 |
+...........+......+............+.................+
+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.50 |
| Brisbane | 5905 | 1857594 | 1146.40 |
| Darwin | 112 | 120900 | 1714.70 |
| Hobart | 1357 | 205556 | 619.50 |
+-----------+------+------------+-----------------+
+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.50 |
| Brisbane | 5905 | 1857594 | 1146.40 |
| Darwin | 112 | 120900 | 1714.70 |
| Hobart | 1357 | 205556 | 619.50 |
+-----------+------+------------+-----------------+