如何根據openpyxl中的值（負值或正值）更改圖表顏色？

Question

基於在openpyxl值（負或正值）如何更改圖表的顏色？
真的很難爲我。

from openpyxl import Workbook 
from openpyxl.styles import Border, Side, PatternFill, Font, GradientFill,Alignment, Color, numbers 
from openpyxl.chart import BarChart, Reference 

book = Workbook() 
sheet = book.active 
rows = [ 
['Number', 'Batch 1'], 
['a', 40], 
['b', -40], 
['c', 50], 
['d', -30], 
['e', -25], 
['f', 30], 
] 

for row in rows: 
    sheet.append(row) 

chart = BarChart() 
chartCats = Reference(sheet, min_col=1, min_row=2, max_row=7) 
chartData = Reference(sheet, min_col=2, min_row=1, max_col=2, max_row=7) 
chart.add_data(chartData, titles_from_data = True) 
chart.set_categories(chartCats) 
chart.type = 'bar' 
chart.style = 27 
chart.height = 10 
chart.width = 15 
chart.legend = None 
chart.x_axis.tickLblPos = "low" 
chart.y_axis.number_format = '#,##0' 
chart.y_axis.majorGridlines = None 
sheet.add_chart(chart, 'A1') 
book.save('test.xlsx') 

上面的代碼創建標題爲「Batch1」的圖表。但我想要「Batch2」，其中負值和正值顯示不同的顏色。

Answer 1

這目前無法與openpyxl來完成。按照https://www.extendoffice.com/documents/excel/2218-excel-chart-negative-values-different-color.html的說明，我在Excel中創建了一個圖表，並將差異格式應用於數據系列。雖然openpyxl確實支持系列invertIfNegative屬性，原來的OOXML規範不允許其他顏色的數據系列。這是通過對原始規範的擴展來完成的。