How do I create unrollable columns in the Python IDE?

Grouping and ungrouping (also referred to as "rolling up" or "unrolling") column data is a hugely important part of staying organized when working with Deephaven. However, since Deephaven's engine is built in Java, the ungroup method only works on Java arrays - for example, the following query will fail:

offsets = [1, 2, 3, 4]
table = tabe.update("offsets = offsets")
table.ungroup("offsets")

The offsets need to be converted to a Java array for the ungroup method to work:

from deephaven import empty_table
from deephaven import dtypes

offsets = [1, 2, 3, 4]
offsets = dtypes.array(dtypes.int64, offsets)

t1 = empty_table(10).update("X = i")
t2 = t1.update("Offsets=offsets")
t3 = t2.ungroup()
t4 = t2.ungroup("Offsets")

note

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