def dropSmall(df):
    list = []
    for i in df.columns: #b, c, z ..
        if i != 'valeur' and i!='unite':
            list.append(i)
            # iterating on rows
            for j in range(df.groupby(list).sum().shape[0]):
                myMax = df.groupby(list).sum().iloc[:, 0].max() / 30
                myJ = df.groupby(list).sum().iloc[:, 0][j]
                myDf = df.groupby(list).sum().iloc[:, 0]
                if myJ <= myMax:
                    df = df[myDf['value']>=  myMax]

name          b   c   z   l   sL  value       unit
3099    Myindicator     1   1   3   NA  NA  129.74      kg
3100                                    1   44929.74    kg
3101                                    2   5174.74     kg
3110                    3   1   3   1   NA  2497.66     kg
3156                                2   NA  29.43       kg
3222                                3   NA  304.81      kg