time function

[ValeryOchkov]

Is time function again built but not in the function list?

Val
http://twt.mpei.ac.ru/ochkov/v_ochkov.htm

[mzeftel]

The time function is listed under Special Functions.

Mona

[ValeryOchkov]

On 9/9/2009 4:55:41 PM, MonaZ wrote:
>The time function is listed
>under Special Functions.
>
>Mona

OK! Thanks.
But it will be good than yhe time function returns value with time units and do not uses one argument:
time=39.617...yr

Val
http://twt.mpei.ac.ru/ochkov/v_ochkov.htm

[StuartBruff]

On 9/10/2009 12:43:52 AM, VFO wrote:
>== But it will be good than yhe time function
returns value with time units and do not uses one
argument: time=39.617...yr

Good idea, Val, but perhaps use 'Time' for this
purpose to avoid any backward compatibility
problems?

Stuart

[radair]

>But it will be good than yhe time
>function returns value with time units
>and do not uses one argument:
>time=39.617...yr
>
>Val
>http://twt.mpei.ac.ru/ochkov/v_ochkov.ht
>m

The reason to allow time to have a dummy argument is to force it to calclate when that argument changes value. For example,

x = 1

t0 = time(x)
y = x
t1= time(x)

This setup allows t0 and t1 to be synched to y. Without the dummy argument, t0 and t1 would only be calculated once.

Robert

[IRstuff]

Mathcad traditionally recalculates everything from the top to the visible window, regardless of whether anything changed.


TTFN,
Eden

[StuartBruff]

On 9/10/2009 3:41:31 PM, eden_mei wrote:
== Mathcad traditionally recalculates everything from the top to the visible window, regardless of whether anything changed.

I don't think so. It recalculates those things that need changing. I've often resorted (as in the worksheet in this thread) to putting a parameter in time to force it to evaluate along with changes to a variable.

Stuart

[radair]

There's probably a bit of an issue here between what could be done and what is currently done as far as function updates. Currently, I think implementing time without a dummy variable would act like rnd. rnd(1) doesn't get updated each time the worksheet recalculates unless the cursor is sitting inside the function so that it appears to be modified.

I have created functions that get marked as "dirty" each time they calculate using controls, but automatic mode gets a bit of a headache trying to figure out when to stop computation. The dummy variable solves that issue, but that doesn't mean it's the only solution.

Robert