Help needed: optimizing dictionary creation/access

[Pekka Niiranen]

Hmm,

does not using tuple (name, keyp, cost) as key make access time linear?

-pekka-

Peter Otten wrote:

> Pekka Niiranen wrote:
> 
> 
>>def update(p_name, p_keyp, p_cost, p_unit, data):
>>     t = time.asctime()
>>     if data.has_key(p_name):
>>         if data[p_name].has_key(p_keyp):
>>             if data[p_name][p_keyp].has_key(p_cost):
>>                 if p_unit > data[p_name][p_keyp][p_cost][0]:
>>                     data[p_name][p_keyp][p_cost] = [p_unit, t]
>>             else:
>>                 data[p_name][p_keyp][p_cost] = [p_unit, t]
>>         else:
>>             data[p_name][p_keyp] = {p_cost: [p_unit, t]}
>>     else:
>>         data[p_name] = {p_keyp: {p_cost: [p_unit, t]}}
>>     return data
>>
> 
> 
> Untested:
> 
> def update(name, keyp, cost, unit, root):
>     data = root.setdefault(name, {})
>     data = data.setdefault(keyp, {})
>     oldunit = data.get(cost, None)
>     if oldunit:
>         if unit > oldunit[0]:
>             oldunit[:] = [unit, time.asctime()]
>     else:
>         data[cost] = [unit, time.asctime()]
> 
>     return root
> 
> You might consider using a single dictionary with (name, keyp, cost) tuples
> as keys.
> 
> Peter
>