ufl team mailing list archive

[Martin Sandve Alnæs <martinal@xxxxxxxxx>]

On Wed, Feb 4, 2009 at 2:24 PM, Johan Hake <hake@xxxxxxxxx> wrote:
> On Wednesday 04 February 2009 14:15:16 Martin Sandve Alnæs wrote:
>> On Wed, Feb 4, 2009 at 2:12 PM, Johan Hake <hake@xxxxxxxxx> wrote:
>> > On Wednesday 04 February 2009 10:42:12 Martin Sandve Alnæs wrote:
>> >> I won't change the code everywhere to do this now,
>> >> but if profiling in the future shows all the ufl_assert
>> >> calls to take significant time, we can do this:
>> >>
>> >>   isinstance(a, Expr) or error("Expecting Expr instance.")
>> >>
>> >> instead of this:
>> >>
>> >>   ufl_assert(isinstance(a, Expr), "Expecting Expr instance.")
>> >>
>> >> They do exactly the same, the length is about the same,
>> >> but the former is much cheaper as long as it doesn't trigger.
>> >
>> > Some annoying questions ;)
>> >
>> > How much is much and how does this compare to all other things you are
>> > doing?
>> >
>> > Johan
>>
>> 1) I haven't measured, but function calls are expensive and with the
>> ufl_assert approach the function is entered every time.
>>
>> 2) Don't know, which is why I wrote "if profiling ..."
>
> Ok :)

About a factor 4 in a simplified case.
The reason we may want to optimize this is
that almost every operation does assertions.

Martin