python 绘制ks

from pandas import *
import matplotlib.pyplot as plt
def PlotKS(preds, labels, n, asc):
    
    # preds is score: asc=1
    # preds is prob: asc=0
    
    pred = preds  # 预测值
    bad = labels  # 取1为bad, 0为good
    ksds = DataFrame({'bad': bad, 'pred': pred})
    ksds['good'] = 1 - ksds.bad
    
    if asc == 1:
        ksds1 = ksds.sort_values(by=['pred', 'bad'], ascending=[True, True])
    elif asc == 0:
        ksds1 = ksds.sort_values(by=['pred', 'bad'], ascending=[False, True])
    ksds1.index = range(len(ksds1.pred))
    ksds1['cumsum_good1'] = 1.0*ksds1.good.cumsum()/sum(ksds1.good)
    ksds1['cumsum_bad1'] = 1.0*ksds1.bad.cumsum()/sum(ksds1.bad)
    
    if asc == 1:
        ksds2 = ksds.sort_values(by=['pred', 'bad'], ascending=[True, False])
    elif asc == 0: