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set_input for one period leaves the variable's cached sum or twelfth over an overlapping period in place

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#579 0 comentarios 0 reacciones 0 asignados Ver en GitHub

Los mantenedores suelen responder en 2 días

@MaxGhenis ya está trabajando en esto.

Desde el 6/10/2026.

  • #593 de @MaxGhenis — abierto

Evaluación

Dificultad
4/5
Tiempo estimado
3-5 días
Aptitud para principiantes
68/100
Tipo de issue
Error
Claridad
Bien especificado
Estado de actividad
Activo
Stack tecnológico
python
Área
backend, performance

Línea de trabajo

Start by tracing Holder.set_input and Holder._set, then follow Simulation.calculate_add, calculate_divide, and _calculate to understand how overlapping periods and branches are cached. Reproduce the four calculation sequences in the issue; done means setting an input for its own period no longer leaves stale sums or twelfths while existing cache behavior remains intact.

Escrito por el modelo de indexación a partir del texto del issue.

Descripción

set_input for one of a variable's own periods (one month of a monthly variable, one year of a yearly one) replaces the value stored for that period, but leaves in place what the simulation had calculated from it for the same variable at periods of another size: the sum calculate caches for a monthly flow over a year, and the twelfth it caches for a yearly flow at a month. A later calculate returns the cached value, so the result depends on whether the longer (or shorter) period was read before the input was set.

Executed on master b78b0ba9 (two people, formula-less float variables, auto_carry_over_input_variables off):

Steps Result
calculate("flow_m", "2013"); set_input("flow_m", "2013-05", [50, 0]); calculate("flow_m", "2013") [0, 0]
set_input("flow_m", "2013-05", [50, 0]); calculate("flow_m", "2013") [50, 0]
calculate("flow_y", "2013-05"); set_input("flow_y", "2013", [1200, 0]); calculate("flow_y", "2013-05") [0, 0]
set_input("flow_y", "2013", [1200, 0]); calculate("flow_y", "2013-05") [100, 0]

flow_m is a monthly float variable and flow_y a yearly one, both with no formula.

Where it comes from: Simulation.calculate_add stores the sum at the requested period and calculate_divide stores the twelfth at the month (holder.put_in_cache(result, period, self.branch_name)), and _calculate returns a stored value for the requested period before anything else. Holder.set_input with a period of the variable's own unit calls Holder._set for that period only.

The inputs set over a longer period through set_input_divide_by_period and set_input_dispatch_by_period have the same problem and more; the PR for those helpers drops the variable's calculated sums and twelfths that overlap the input period. This issue is the remaining path: an input for the variable's own period. The same rule would fix it (an input drops the values calculated for that variable at overlapping periods of another size, on the branch it is stored under and the branches read through it), applied in Holder.set_input.

Not covered by #571 (which keeps the cache for a flow read over a period of another unit), #566/#576 (the fast cache, not holder storage) or #560 (other variables calculated from the input, on branches).

Lenguaje dominante
Python
Estrellas
22
Forks
30
Merge medio
2 d 21 h
PR fusionados (30 d)
24

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Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
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  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

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