Python 2.7 - modifier les valeurs d'un dataframe pandas basé sur la valeur de la cellule entraîne des données ne pas à tracer correctement - Stack Overflow

I have a data set in which negative values exist, these are indicative of incorrect measurements.

I've tried to set these values to 0 using:

gTemp36[gTemp36['S22  50cm'] < -99]= 0

However when I try to plot this data the graph doesn't plot correctly as shown here (the graph on the right).

I've tried using .dropna() on the DataFrame before plotting but it doesn't seem to improve things, does anybody have any suggestions?

Thanks

set them to nan instead of zero, your plot correctly plots them at zero.

I have a data set in which negative values exist, these are indicative of incorrect measurements.

I've tried to set these values to 0 using:

gTemp36[gTemp36['S22  50cm'] < -99]= 0

However when I try to plot this data the graph doesn't plot correctly as shown here (the graph on the right).

I've tried using .dropna() on the DataFrame before plotting but it doesn't seem to improve things, does anybody have any suggestions?

Thanks

set them to nan instead of zero, your plot correctly plots them at zero.

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