I try to modify the value of cells in a dataframe, conditionnal to their value.
the dataframe dataTrad(50k, 20) as 21 columns, one of which is called 'reindex'.
I want to bring the value of any 'reindex' cell down to 0 as soon as its original value is lower than a variable (mlp).

I tried : `dataTrad[i, 'reindex'][dataTrad[i, 'reindex'] < mlp] = 0` with a loop on i with the range(len(dataTrad)),
as well as `dataTrad.loc[(dataTrad.reindex < malp),'reindex']=0`, but none of these two methods worked.

In my precise example, I had mlp = 60 len(dataTrad) = 57830

What do I do wrong, and how could I solve this ?
Thanks a lot in advance.