Python Pandas-添加一列，该列的值根据当前行和上一行中的另一列值计算

鉴于下面的数据框架

colNames = ["Time","Col2","Col3","Col4","Col5","Col6","Col7","Col8","Col9","Col10","Col11","Col12","Col13"]
colVals = [['05:17:55.703', '', '', '', '', '', '21', '', '3', '89', '891', '11', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '12', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '13', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '15', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '16', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '17', ''], ['05:17:55.703', '', '', '', '', '', '21', '', '3', '217', '891', '18', ''], ['05:17:55.707', '', '', '', '', '', '18', '', '3', '185', '892', '0', ''], ['05:17:55.707', '', '', '', '', '', '21', '', '3', '185', '892', '1', ''], ['05:17:55.707', '', '', '', '', '', '17', '', '3', '73', '892', '5', ''], ['05:17:55.707', '', '', '', '', '', '17', '', '3', '185', '892', '6', ''], ['05:17:55.707', '', '', '', '', '', '21', '', '3', '73', '892', '7', ''], ['05:17:55.708', '268', '4', '28', '-67.60', '13', '', '2', '', '', '', '', '2'], ['05:17:55.711', '', '', '', '', '', '18', '', '3', '57', '892', '10', ''], ['05:17:55.711', '', '', '', '', '', '21', '', '3', '201', '892', '11', ''], ['05:17:55.711', '', '', '', '', '', '21', '', '3', '25', '892', '12', ''], ['05:17:55.723', '', '', '', '', '', '21', '', '3', '217', '893', '11', ''], ['05:17:55.723', '', '', '', '', '', '21', '', '3', '217', '893', '15', ''], ['05:17:55.723', '', '', '', '', '', '21', '', '3', '217', '893', '16', ''], ['05:17:55.726', '268', '4', '', '-67.80', '', '', '', '', '', '', '', ''], ['05:17:55.728', '', '', '28', '', '12', '31', '2', '3', '185', '894', '0', '1'], ['05:17:55.728', '', '', '', '', '', '31', '', '3', '185', '894', '1', ''], ['05:17:55.731', '', '', '', '', '', '31', '', '3', '217', '894', '10', ''], ['05:17:55.731', '', '', '', '', '', '20', '', '3', '217', '894', '11', ''], ['05:17:55.731', '', '', '', '', '', '20', '', '3', '217', '894', '12', ''], ['05:17:55.731', '', '', '', '', '', '20', '', '3', '217', '894', '13', ''], ['05:17:55.743', '', '', '', '', '', '20', '', '3', '217', '895', '11', ''], ['05:17:55.743', '', '', '', '', '', '20', '', '3', '217', '895', '15', ''], ['05:17:55.743', '', '', '', '', '', '20', '', '3', '217', '895', '16', ''], ['05:17:55.746', '268', '4', '', '-67.82', '', '', '', '', '', '', '', ''], ['05:17:55.747', '', '', '28', '', '13', '20', '2', '3', '185', '896', '1', '2'], ['05:17:55.747', '', '', '', '', '', '20', '', '3', '185', '896', '2', ''], ['05:17:55.747', '', '', '', '', '', '30', '', '3', '217', '896', '5', ''], ['05:17:55.751', '', '', '', '', '', '18', '', '3', '217', '896', '10', ''], ['05:17:55.751', '', '', '', '', '', '21', '', '3', '217', '896', '11', ''], ['05:17:55.751', '', '', '', '', '', '21', '', '3', '217', '896', '12', ''], ['05:17:55.751', '', '', '', '', '', '21', '', '3', '217', '896', '13', ''], ['05:17:55.763', '', '', '', '', '', '31', '', '3', '217', '897', '11', ''], ['05:17:55.763', '', '', '', '', '', '30', '', '3', '217', '897', '15', ''], ['05:17:55.763', '', '', '', '', '', '20', '', '3', '217', '897', '16', ''], ['05:17:55.763', '', '', '', '', '', '20', '', '3', '217', '897', '17', ''], ['05:17:55.766', '268', '4', '', '-67.13', '', '', '', '', '', '', '', ''], ['05:17:55.768', '', '', '28', '', '12', '20', '2', '3', '185', '898', '3', '2'], ['05:17:55.768', '', '', '', '', '', '16', '', '3', '217', '898', '6', ''], ['05:17:55.771', '', '', '', '', '', '18', '', '3', '217', '898', '10', ''], ['05:17:55.771', '', '', '', '', '', '20', '', '3', '217', '898', '11', ''], ['05:17:55.771', '', '', '', '', '', '20', '', '3', '217', '898', '12', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '217', '899', '11', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '41', '899', '12', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '25', '899', '13', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '217', '899', '15', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '217', '899', '16', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '217', '899', '17', ''], ['05:17:55.784', '', '', '', '', '', '20', '', '3', '217', '899', '18', ''], ['05:17:55.786', '268', '4', '', '-67.66', '', '', '', '', '', '', '', ''], ['05:17:55.788', '', '', '28', '', '13', '18', '2', '3', '185', '900', '0', '2'], ['05:17:55.788', '', '', '', '', '', '20', '', '3', '185', '900', '1', ''], ['05:17:55.788', '', '', '', '', '', '20', '', '3', '185', '900', '2', ''], ['05:17:55.788', '', '', '', '', '', '16', '', '3', '41', '900', '5', ''], ['05:17:55.788', '', '', '', '', '', '17', '', '3', '185', '900', '6', ''], ['05:17:55.791', '', '', '', '', '', '20', '', '3', '105', '900', '7', ''], ['05:17:55.791', '', '', '', '', '', '20', '', '3', '89', '900', '8', ''], ['05:17:55.791', '', '', '', '', '', '18', '', '3', '217', '900', '10', ''], ['05:17:55.791', '', '', '', '', '', '20', '', '3', '217', '900', '11', ''], ['05:17:55.791', '', '', '', '', '', '20', '', '3', '25', '900', '12', ''], ['05:17:55.806', '268', '4', '', '-67.50', '', '', '', '', '', '', '', ''], ['05:17:55.808', '', '', '28', '', '12', '31', '2', '3', '185', '902', '0', '1'], ['05:17:55.808', '', '', '', '', '', '31', '', '3', '185', '902', '1', ''], ['05:17:55.808', '', '', '', '', '', '20', '', '3', '25', '902', '2', ''], ['05:17:55.808', '', '', '', '', '', '20', '', '3', '25', '902', '3', ''], ['05:17:55.808', '', '', '', '', '', '16', '', '3', '217', '902', '5', ''], ['05:17:55.808', '', '', '', '', '', '16', '', '3', '217', '902', '6', ''], ['05:17:55.811', '', '', '', '', '', '20', '', '3', '89', '902', '7', ''], ['05:17:55.811', '', '', '', '', '', '20', '', '3', '121', '902', '8', ''], ['05:17:55.811', '', '', '', '', '', '18', '', '3', '217', '902', '10', ''], ['05:17:55.811', '', '', '', '', '', '20', '', '3', '217', '902', '11', ''], ['05:17:55.811', '', '', '', '', '', '20', '', '3', '73', '902', '12', ''], ['05:17:55.811', '', '', '', '', '', '20', '', '3', '9', '902', '15', ''], ['05:17:55.815', '', '', '', '', '', '20', '', '3', '217', '902', '16', ''], ['05:17:55.815', '', '', '', '', '', '20', '', '3', '25', '902', '17', ''], ['05:17:55.815', '', '', '', '', '', '20', '', '3', '217', '902', '18', ''], ['05:17:55.815', '', '', '', '', '', '18', '', '3', '217', '903', '0', ''], ['05:17:55.815', '', '', '', '', '', '21', '', '3', '217', '903', '1', ''], ['05:17:55.815', '', '', '', '', '', '19', '', '3', '105', '903', '2', ''], ['05:17:55.815', '', '', '', '', '', '21', '', '3', '41', '903', '3', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '217', '903', '11', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '9', '903', '12', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '105', '903', '13', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '217', '903', '15', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '217', '903', '16', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '121', '903', '17', ''], ['05:17:55.823', '', '', '', '', '', '21', '', '3', '89', '903', '18', ''], ['05:17:55.826', '268', '4', '', '-67.51', '', '', '', '', '', '', '', ''], ['05:17:55.828', '', '', '28', '', '12', '18', '2', '3', '185', '904', '0', '1'], ['05:17:55.828', '', '', '', '', '', '21', '', '3', '185', '904', '1', ''], ['05:17:55.828', '', '', '', '', '', '21', '', '3', '185', '904', '2', ''], ['05:17:55.828', '', '', '', '', '', '21', '', '3', '185', '904', '3', ''], ['05:17:55.828', '', '', '', '', '', '17', '', '3', '217', '904', '5', ''], ['05:17:55.828', '', '', '', '', '', '17', '', '3', '217', '904', '6', ''], ['05:17:55.831', '', '', '', '', '', '21', '', '3', '217', '904', '7', ''], ['05:17:55.831', '', '', '', '', '', '20', '', '3', '169', '904', '11', ''], ['05:17:55.831', '', '', '', '', '', '20', '', '3', '217', '904', '12', ''], ['05:17:55.831', '', '', '', '', '', '20', '', '3', '217', '904', '13', ''], ['05:17:55.846', '268', '4', '', '-67.01', '', '', '', '', '', '', '', ''], ['05:17:55.848', '', '', '28', '', '13', '19', '2', '3', '57', '906', '1', '2'], ['05:17:55.848', '', '', '', '', '', '19', '', '3', '41', '906', '2', ''], ['05:17:55.848', '', '', '', '', '', '19', '', '3', '73', '906', '3', ''], ['05:17:55.848', '', '', '', '', '', '16', '', '3', '217', '906', '5', ''], ['05:17:55.848', '', '', '', '', '', '16', '', '3', '217', '906', '6', ''], ['05:17:55.848', '', '', '', '', '', '19', '', '3', '9', '906', '7', ''], ['05:17:55.851', '', '', '', '', '', '20', '', '3', '121', '906', '11', ''], ['05:17:55.851', '', '', '', '', '', '20', '', '3', '57', '906', '12', ''], ['05:17:55.851', '', '', '', '', '', '20', '', '3', '105', '906', '13', ''], ['05:17:55.855', '', '', '', '', '', '20', '', '3', '217', '906', '15', ''], ['05:17:55.855', '', '', '', '', '', '20', '', '3', '217', '906', '16', ''], ['05:17:55.855', '', '', '', '', '', '20', '', '3', '105', '906', '17', ''], ['05:17:55.855', '', '', '', '', '', '17', '', '3', '185', '907', '0', ''], ['05:17:55.855', '', '', '', '', '', '20', '', '3', '217', '907', '1', ''], ['05:17:55.855', '', '', '', '', '', '20', '', '3', '9', '907', '2', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '217', '907', '11', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '57', '907', '12', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '153', '907', '13', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '217', '907', '15', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '217', '907', '16', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '57', '907', '17', ''], ['05:17:55.864', '', '', '', '', '', '20', '', '3', '105', '907', '18', ''], ['05:17:55.867', '', '', '', '', '', '17', '', '3', '185', '908', '0', ''], ['05:17:55.867', '', '', '', '', '', '20', '', '3', '185', '908', '1', ''], ['05:17:55.867', '', '', '', '', '', '20', '', '3', '9', '908', '2', ''], ['05:17:55.867', '', '', '', '', '', '16', '', '3', '73', '908', '6', ''], ['05:17:55.868', '268', '4', '28', '-66.79', '13', '', '2', '', '', '', '', '2'], ['05:17:55.871', '', '', '', '', '', '20', '', '3', '105', '908', '7', ''], ['05:17:55.871', '', '', '', '', '', '20', '', '3', '25', '908', '8', ''], ['05:17:55.871', '', '', '', '', '', '17', '', '3', '217', '908', '10', ''], ['05:17:55.871', '', '', '', '', '', '21', '', '3', '217', '908', '11', ''], ['05:17:55.871', '', '', '', '', '', '21', '', '3', '9', '908', '12', ''], ['05:17:55.871', '', '', '', '', '', '21', '', '3', '121', '908', '13', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '217', '908', '15', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '217', '908', '16', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '57', '908', '17', ''], ['05:17:55.875', '', '', '', '', '', '18', '', '3', '73', '909', '0', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '217', '909', '1', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '89', '909', '2', ''], ['05:17:55.875', '', '', '', '', '', '21', '', '3', '89', '909', '3', ''], ['05:17:55.886', '268', '4', '', '-67.48', '', '', '', '', '', '', '', ''], ['05:17:55.888', '', '', '28', '', '12', '31', '2', '3', '185', '910', '0', '1'], ['05:17:55.888', '', '', '', '', '', '21', '', '3', '89', '910', '1', ''], ['05:17:55.888', '', '', '', '', '', '21', '', '3', '9', '910', '2', ''], ['05:17:55.888', '', '', '', '', '', '21', '', '3', '185', '910', '3', ''], ['05:17:55.888', '', '', '', '', '', '17', '', '3', '217', '910', '5', ''], ['05:17:55.888', '', '', '', '', '', '17', '', '3', '217', '910', '6', ''], ['05:17:55.891', '', '', '', '', '', '21', '', '3', '89', '910', '7', ''], ['05:17:55.891', '', '', '', '', '', '21', '', '3', '73', '910', '8', ''], ['05:17:55.891', '', '', '', '', '', '18', '', '3', '217', '910', '10', ''], ['05:17:55.891', '', '', '', '', '', '21', '', '3', '217', '910', '11', ''], ['05:17:55.891', '', '', '', '', '', '21', '', '3', '57', '910', '12', ''], ['05:17:55.900', '', '', '', '', '', '21', '', '3', '217', '911', '3', ''], ['05:17:55.900', '', '', '', '', '', '17', '', '3', '217', '911', '5', ''], ['05:17:55.900', '', '', '', '', '', '17', '', '3', '217', '911', '6', ''], ['05:17:55.900', '', '', '', '', '', '21', '', '3', '105', '911', '7', ''], ['05:17:55.900', '', '', '', '', '', '21', '', '3', '25', '911', '8', ''], ['05:17:55.900', '', '', '', '', '', '18', '', '3', '217', '911', '10', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '217', '911', '11', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '57', '911', '12', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '153', '911', '13', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '217', '911', '15', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '217', '911', '16', ''], ['05:17:55.903', '', '', '', '', '', '21', '', '3', '137', '911', '17', ''], ['05:17:55.906', '268', '4', '', '-67.79', '', '', '', '', '', '', '', ''], ['05:17:55.908', '', '', '28', '', '13', '18', '2', '3', '57', '912', '0', '2'], ['05:17:55.908', '', '', '', '', '', '21', '', '3', '185', '912', '1', ''], ['05:17:55.908', '', '', '', '', '', '21', '', '3', '57', '912', '2', ''], ['05:17:55.908', '', '', '', '', '', '17', '', '3', '137', '912', '5', ''], ['05:17:55.908', '', '', '', '', '', '17', '', '3', '169', '912', '6', ''], ['05:17:55.923', '', '', '', '', '', '21', '', '3', '217', '913', '11', ''], ['05:17:55.923', '', '', '', '', '', '21', '', '3', '89', '913', '12', ''], ['05:17:55.926', '268', '4', '', '-68.13', '', '', '', '', '', '', '', ''], ['05:17:55.928', '', '', '28', '', '13', '31', '2', '3', '185', '914', '0', '2'], ['05:17:55.928', '', '', '', '', '', '21', '', '3', '105', '914', '2', ''], ['05:17:55.928', '', '', '', '', '', '17', '', '3', '25', '914', '5', ''], ['05:17:55.928', '', '', '', '', '', '17', '', '3', '121', '914', '6', ''], ['05:17:55.928', '', '', '', '', '', '21', '', '3', '25', '914', '7', ''], ['05:17:55.931', '', '', '', '', '', '18', '', '3', '89', '914', '10', ''], ['05:17:55.931', '', '', '', '', '', '21', '', '3', '217', '914', '11', ''], ['05:17:55.931', '', '', '', '', '', '21', '', '3', '73', '914', '12', ''], ['05:17:55.939', '', '', '', '', '', '17', '', '3', '137', '915', '5', ''], ['05:17:55.939', '', '', '', '', '', '17', '', '3', '153', '915', '6', ''], ['05:17:55.939', '', '', '', '', '', '21', '', '3', '73', '915', '7', ''], ['05:17:55.939', '', '', '', '', '', '18', '', '3', '153', '915', '10', ''], ['05:17:55.943', '', '', '', '', '', '21', '', '3', '217', '915', '11', ''], ['05:17:55.943', '', '', '', '', '', '21', '', '3', '137', '915', '12', ''], ['05:17:55.943', '', '', '', '', '', '21', '', '3', '137', '915', '15', ''], ['05:17:55.943', '', '', '', '', '', '21', '', '3', '217', '915', '16', ''], ['05:17:55.943', '', '', '', '', '', '21', '', '3', '105', '915', '17', ''], ['05:17:55.946', '268', '4', '', '-67.45', '', '', '', '', '', '', '', ''], ['05:17:55.948', '', '', '28', '', '9', '30', '3', '3', '160', '916', '0', '3'], ['05:17:55.948', '', '', '', '', '', '21', '', '3', '121', '916', '1', ''], ['05:17:55.948', '', '', '', '', '', '21', '', '3', '105', '916', '2', ''], ['05:17:55.948', '', '', '', '', '', '17', '', '3', '73', '916', '5', ''], ['05:17:55.948', '', '', '', '', '', '17', '', '3', '137', '916', '6', ''], ['05:17:55.959', '', '', '', '', '', '13', '', '4', '217', '917', '3', ''], ['05:17:55.959', '', '', '', '', '', '11', '', '4', '217', '917', '5', ''], ['05:17:55.959', '', '', '', '', '', '11', '', '4', '217', '917', '6', ''], ['05:17:55.959', '', '', '', '', '', '13', '', '4', '217', '917', '7', ''], ['05:17:55.959', '', '', '', '', '', '13', '', '4', '217', '917', '8', ''], ['05:17:55.959', '', '', '', '', '', '11', '', '4', '153', '917', '10', ''], ['05:17:55.963', '', '', '', '', '', '13', '', '4', '217', '917', '11', ''], ['05:17:55.963', '', '', '', '', '', '13', '', '4', '121', '917', '12', ''], ['05:17:55.966', '268', '4', '', '-67.22', '', '', '', '', '', '', '', ''], ['05:17:55.968', '', '', '28', '', '12', '14', '2', '4', '57', '918', '1', '2'], ['05:17:55.968', '', '', '', '', '', '14', '', '4', '185', '918', '2', ''], ['05:17:55.968', '', '', '', '', '', '12', '', '4', '169', '918', '5', ''], ['05:17:55.983', '', '', '', '', '', '14', '', '4', '57', '919', '11', ''], ['05:17:55.983', '', '', '', '', '', '14', '', '4', '217', '919', '12', ''], ['05:17:55.983', '', '', '', '', '', '14', '', '4', '9', '919', '15', ''], ['05:17:55.983', '', '', '', '', '', '14', '', '4', '217', '919', '16', ''], ['05:17:55.983', '', '', '', '', '', '14', '', '4', '217', '919', '17', ''], ['05:17:55.986', '268', '4', '', '-67.80', '', '', '', '', '', '', '', ''], ['05:17:55.988', '', '', '28', '', '13', '14', '2', '4', '9', '920', '1', '1'], ['05:17:55.988', '', '', '', '', '', '14', '', '4', '41', '920', '2', ''], ['05:17:55.988', '', '', '', '', '', '14', '', '4', '57', '920', '3', ''], ['05:17:55.988', '', '', '', '', '', '12', '', '4', '217', '920', '5', ''], ['05:17:55.988', '', '', '', '', '', '12', '', '4', '217', '920', '6', ''], ['05:17:55.988', '', '', '', '', '', '14', '', '4', '41', '920', '7', ''], ['05:17:55.991', '', '', '', '', '', '14', '', '4', '89', '920', '8', ''], ['05:17:55.991', '', '', '', '', '', '22', '', '3', '217', '920', '11', ''], ['05:17:55.991', '', '', '', '', '', '22', '', '3', '89', '920', '12', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '25', '921', '11', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '121', '921', '12', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '25', '921', '13', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '217', '921', '15', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '217', '921', '16', ''], ['05:17:56.003', '', '', '', '', '', '22', '', '3', '217', '921', '17', ''], ['05:17:56.006', '268', '4', '', '-67.31', '', '', '', '', '', '', '', ''], ['05:17:56.008', '', '', '28', '', '10', '22', '3', '3', '9', '922', '1', '3'], ['05:17:56.008', '', '', '', '', '', '22', '', '3', '73', '922', '2', ''], ['05:17:56.008', '', '', '', '', '', '17', '', '3', '121', '922', '5', ''], ['05:17:56.008', '', '', '', '', '', '17', '', '3', '185', '922', '6', ''], ['05:17:56.011', '', '', '', '', '', '22', '', '3', '217', '922', '7', ''], ['05:17:56.011', '', '', '', '', '', '22', '', '3', '121', '922', '11', ''], ['05:17:56.011', '', '', '', '', '', '22', '', '3', '89', '922', '12', ''], ['05:17:56.020', '', '', '', '', '', '17', '', '3', '105', '923', '5', ''], ['05:17:56.020', '', '', '', '', '', '17', '', '3', '185', '923', '6', ''], ['05:17:56.020', '', '', '', '', '', '22', '', '3', '25', '923', '7', ''], ['05:17:56.020', '', '', '', '', '', '31', '', '3', '112', '923', '10', ''], ['05:17:56.023', '', '', '', '', '', '31', '', '3', '112', '923', '11', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '12', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '13', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '15', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '16', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '17', ''], ['05:17:56.023', '', '', '', '', '', '22', '', '3', '217', '923', '18', ''], ['05:17:56.027', '', '', '', '', '', '18', '', '3', '57', '924', '0', ''], ['05:17:56.027', '', '', '', '', '', '22', '', '3', '41', '924', '1', ''], ['05:17:56.027', '', '', '', '', '', '22', '', '3', '185', '924', '2', ''], ['05:17:56.027', '', '', '', '', '', '22', '', '3', '185', '924', '3', ''], ['05:17:56.027', '', '', '', '', '', '17', '', '3', '73', '924', '5', ''], ['05:17:56.027', '', '', '', '', '', '17', '', '3', '217', '924', '6', ''], ['05:17:56.028', '268', '4', '28', '-67.68', '13', '', '2', '', '', '', '', '2'], ['05:17:56.039', '', '', '', '', '', '22', '', '3', '217', '925', '3', ''], ['05:17:56.039', '', '', '', '', '', '17', '', '3', '217', '925', '5', ''], ['05:17:56.039', '', '', '', '', '', '17', '', '3', '217', '925', '6', ''], ['05:17:56.039', '', '', '', '', '', '22', '', '3', '217', '925', '7', ''], ['05:17:56.039', '', '', '', '', '', '18', '', '3', '57', '925', '10', ''], ['05:17:56.043', '', '', '', '', '', '22', '', '3', '73', '925', '16', '']]

df = pd.DataFrame(colVals, columns=colNames)
df = df.set_index('Time')
df = df.apply(pd.to_numeric, errors='coerce')

需要添加新的

Col14

，以便当前行的

Col11

中的值小于前一行的

Col11

中的值时，它从0开始递增1-如果前一行的

Col11

值为

NaN

，则不应递增

Col14

比如说

+-------+-------+-------------------------------------------------------------------------------------------------+
| Col11 | Col14 |                                                                                                 |
+-------+-------+-------------------------------------------------------------------------------------------------+
| 900   |     0 | start with 0                                                                                    |
| NaN   |     0 |                                                                                                 |
| 900   |     0 |                                                                                                 |
| 903   |     0 |                                                                                                 |
| 904   |     0 |                                                                                                 |
| 904   |     0 |                                                                                                 |
| 8     |     1 | increment Col14 by 1 when current row's Col11 value is less than the previous row's Col11 value |
| 8     |     1 |                                                                                                 |
| 200   |     1 |                                                                                                 |
| 201   |     1 |                                                                                                 |
| NaN   |     1 | if Col11 is NaN, Col12 takes same value as prev row                                                                               |
| 0     |     2 | increment Col14 by 1 when current row's Col11 value is less than the previous row's Col11 value |
| 1     |     2 |                                                                                                 |
| NaN   |     2 |                                                                                                 |
| NaN   |     2 |                                                                                                 |
| 0     |     3 | increment Col14 by 1 when current row's Col11 value is less than the previous row's Col11 value |
+-------+-------+-------------------------------------------------------------------------------------------------+

有没有办法获取上一行的引用？

你能试试这个吗

df['col14']=df.Col11.gt(df.Col11.shift(-1)).cumsum()

或

两者的区别在于，计数在较低值的末尾（第一个值）切换，在新值的开头（第二个值）切换

如果你想把NaN与前面的非NaN值一样，下面的代码。< /P>

df['col14b']=df.Col11.fillna(method='ffill').gt(df.Col11.fillna(method='ffill').shift(-1)).shift().fillna(0).cumsum().astype(int)

对于您提供的较小的虚拟数据集，输出如下所示

Col11   col14   col14a  col14b
0   900.0   0   0   0
1   NaN     0   0   0
2   900.0   0   0   0
3   900.0   0   0   0
4   903.0   0   0   0
5   904.0   0   0   0
6   904.0   1   0   0
7   8.0     1   1   1
8   8.0     1   1   1
9   200.0   1   1   1
10  201.0   1   1   1
11  NaN     1   1   1
12  0.0     1   1   2
13  1.0     1   1   2
14  NaN     1   1   2
15  NaN     1   1   2
16  0.0     1   1   3

详细信息 我在这里解释最后一个，其他两个与此类似

使用

df.Col11.fillna（method='ffill'）

我们用以前的有效值填充NaN，因此输出如下（我们没有更改Coll11，我们只是在创建新列时使用它）

使用

df.Col11.fillna（method='ffill'）.shift（-1）

0     900.0
1     900.0
2     900.0
3     903.0
4     904.0
5     904.0
6       8.0
7       8.0
8     200.0
9     201.0
10    201.0
11      0.0
12      1.0
13      1.0
14      1.0
15      0.0
16      NaN

使用

df.Col11.fillna（method='ffill'）.gt（df.Col11.fillna（method='ffill'）.shift（-1））

进行比较&结果为真或假，如下所示

0     False
1     False
2     False
3     False
4     False
5     False
6      True
7     False
8     False
9     False
10    False
11     True
12    False
13    False
14    False
15     True
16    False

---

我们使用

shift

将值向下移动一行，因为您希望在出现较小的数字时切换数字。当我们向下移动行时，第一行变为

NaN

，我们使用

.fillna（0）

将其替换为0（因为我们必须从零开始）。然后我们使用

.cumsum（）

.cumsum（）

仅添加

True

值，因此，我们可以获得所需的值。最后，我们使用

.astype（int）

将此列指定为整数，以使所有值都成为整数。

这不会给出所需的结果<当

Col11

的值低于前一行中的值时，code>Col14应增加。只需将

lt

（小于）更改为

gt

（大于）。代码已更新。但是，似乎没有一行比数据集中前一行中的行少。它会像在更新的较小的虚拟数据集中那样处理NaN吗！！。想解释一下所做的不同操作吗？添加了详细信息。过来看。

0     900.0
1     900.0
2     900.0
3     903.0
4     904.0
5     904.0
6       8.0
7       8.0
8     200.0
9     201.0
10    201.0
11      0.0
12      1.0
13      1.0
14      1.0
15      0.0
16      NaN

0     False
1     False
2     False
3     False
4     False
5     False
6      True
7     False
8     False
9     False
10    False
11     True
12    False
13    False
14    False
15     True
16    False