decimalArith
Same-dtype exact addition/subtraction of DECIMAL columns: one checked step per slot (overflow throws before any result is exposed), nulls propagate, the dtype is unchanged. Multiply, divide and cross-scale arithmetic are not part of the tier and reject at the caller (ADR-2026-10-23-14).
Parameters
op | `"+"` or `"-"` |
a | the left Series |
b | the right Series (same full dtype) |
Returns
the sum/difference Series.
Throws
DataFrameException on any slot's overflow.