我有一个如下所示的数据帧(前3行)：

Sample_Name Sample_ID Sample_Type IS Component_Name IS_Name Component_Group_Name Outlier_Reasons Actual_Concentration Area Height Retention_Time Width_at_50_pct Used Calculated_Concentration Accuracy

Index

1 20170824_ELN147926_HexLacCer_Plasma_A-1-1 NaN Unknown True GluCer(d18:1/12:0)_LCB_264.3 NaN NaN NaN 0.1 2.733532e+06 5.963840e+05 2.963911 0.068676 True NaN NaN

2 20170824_ELN147926_HexLacCer_Plasma_A-1-1 NaN Unknown True GluCer(d18:1/17:0)_LCB_264.3 NaN NaN NaN 0.1 2.945190e+06 5.597470e+05 2.745026 0.068086 True NaN NaN

3 20170824_ELN147926_HexLacCer_Plasma_A-1-1 NaN Unknown False GluCer(d18:1/16:0)_LCB_264.3 GluCer(d18:1/17:0)_LCB_264.3 NaN NaN NaN 3.993535e+06 8.912731e+05 2.791991 0.059864 True 125.927659773487 NaN

尝试生成数据透视表时：

pivoted_report_conc = raw_report.pivot(index = "Sample_Name", columns = 'Component_Name', values = "Calculated_Concentration")

我收到以下错误：

ValueError: Index contains duplicate entries, cannot reshape

我尝试重置索引但它没有帮助.我在“索引”列中找不到任何重复值.有人可以帮忙找出问题吗？

预期的输出将是一个重新整形的数据框,只有唯一的组件名称作为列和每个样本名称的相应浓度：

Sample_Name GluCer(d18:1/12:0)_LCB_264.3 GluCer(d18:1/17:0)_LCB_264.3 GluCer(d18:1/16:0)_LCB_264.3

20170824_ELN147926_HexLacCer_Plasma_A-1-1 NaN NaN 125.927659773487

为了澄清,我不打算聚合数据,只是重塑它.

解决方法:

您可以使用groupby()和unstack()来绕过您在pivot()中看到的错误.

这是一些示例数据,添加了一些边缘情况,并删除了一些列值或替换为MCVE：

# df

Sample_Name Sample_ID IS Component_Name Calculated_Concentration Outlier_Reasons

Index

1 foo NaN True x NaN NaN

1 foo NaN True y NaN NaN

2 foo NaN False z 125.92766 NaN

2 bar NaN False x 1.00 NaN

2 bar NaN False y 2.00 NaN

2 bar NaN False z NaN NaN

(df.groupby(['Sample_Name','Component_Name'])

.Calculated_Concentration

.first()

.unstack()

)

输出：

Component_Name x y z

Sample_Name

bar 1.0 2.0 NaN

foo NaN NaN 125.92766

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