BUG: Unexpected behavior using loc to assign value in a for loop

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Reproducible Example

import pandas

# multiple assignement using index loc like code below (column name may vary)
for ... in ...:
   [...]
   indx_measure_started = df_meas[df_meas.key == something].index
   df_meas.loc[indx_measure_started, "Vitesse Traverse"] = numpy.hstack(([0], numpy.abs(delta_position / delta_t)))

Issue Description

I don’t know why but there is a strange behavior after multiple use of loc for assignement. I’m sorry to not be able to give you a more precise way to reproduce… I tried to debug each line and don’t understand what is happening (may be something in the indexing.py file)

Using a setting value method like

df_meas.loc[indx_measure_started, "Vitesse Traverse"] = numpy.hstack(([0], numpy.abs(delta_position / delta_t)))

I can no more access the value using loc. Note that in the image below if I use loc + iloc I find the computed values…

Is it a kind of memory leaks ?

Expected Behavior

I expect to have the values readable…

TIPS :

• Behaviour as expected with 1.2.5, 1.3.5
• KO for 1.4.0

Installed Versions

Replace this line with the output of 1.4.3

[phofl]

Will close then, please ping to reopen if you have a reproducible example

[jreback]

@jultou-raa if you have a reproducible example you can ping to reopen as was stated above