python柱形图显示年份,Python：条形图-在所有年份中按a）年和b）季度绘制值的总和...
I have time series data, i.e. by date (YYYY-MM-DD), returns, pnl, # of trades:date returns pnl no_trades1998-01-01 0.01 0.05 51998-01-02 -0.04 ...
