問題描述

為了打印表格數據的標題，我只想使用一個格式字符串 line 和一個列寬規范 w1, w2, w3 (如果可能的話，甚至是 w = x, y, z.)

In order to print a header for tabular data, I'd like to use only one format string line and one spec for column widths w1, w2, w3 (or even w = x, y, z if possible.)

我看過 this 但 tabulate 等不要讓我像 format 那樣證明列中的內容.

I've looked at this but tabulate etc. don't let me justify things in the column like format does.

這種方法有效:

head = 'eggs', 'bacon', 'spam'  
w1, w2, w3 = 8, 7, 10  # column widths  
line = '  {:{ul}>{w1}}  {:{ul}>{w2}}  {:{ul}>{w3}}'  
under = 3 * '='  
print line.format(*head, ul='', w1=w1, w2=w2, w3=w3)  
print line.format(*under, ul='=', w1=w1, w2=w2, w3=w3)  

我必須在格式字符串中有單獨的名稱作為寬度 {w1}, {w2}, ...嗎?{w[1]}、{w[2]} 等嘗試給出 KeyError 或 keyword can't be an表達式.

Must I have individual names as widths {w1}, {w2}, ... in the format string? Attempts like {w[1]}, {w[2]}, give either KeyError or keyword can't be an expression.

另外我認為 w1=w1, w2=w2, w3=w3 不是很簡潔.有沒有更好的辦法?

Also I think the w1=w1, w2=w2, w3=w3 is not very succinct. Is there a better way?

推薦答案

這是 jonrsharpe 對我的 OP 的評論，旨在可視化正在發生的事情.

This is jonrsharpe's comment to my OP, worked out so as to visualise what's going on.

line = '  {:{ul}>{w1}}  {:{ul}>{w2}}  {:{ul}>{w3}}'
under = 3 * '_'

head = 'sausage', 'rat', 'strawberry tart'

# manual dict 
v = {'w1': 8, 'w2':5, 'w3': 17}
print line.format(*under, ul='_', **v)

# auto dict
widthl = [8, 7, 9]
x = {'w{}'.format(index): value for index, value in enumerate(widthl, 1)}
print line.format(*under, ul='_', **x)     

關鍵是我希望能夠快速重新排列標題，而無需調整格式字符串.auto dict 很好地滿足了這個要求.

The point is that I want to be able to quickly rearrange the header without having to tweak the format string. The auto dict meets that requirement very nicely.

至于以這種方式填充字典:哇！

As for filling a dict in this way: WOW!

這篇關于Python格式字符串中的寬度變量的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！