how to indentify driving pred./succ.

[doniy]

I'm using MSP2000
I'm trying to build a form to show all pred./succ for the selected task with
more detail information e.g. TF,FF,ES,EF,relation& lag, duration...
and the most important point is to highlight the driving pred./succ, just
like in P3

Now I have creat the form. using listbox to show the preds' detail
information.
But the problem is how to identify which pred. is the driving preds, Does
MSP has some build-in method to identify this, or any idea how to do this?

I'm trying to calculate the start date by using preds' start date,
relationship, lag, calendar, if the the date from my calculation is same as
the date from MSP then i consider this pred driving. is there any better
solution.

another problem is how to get the proper lag, for lag expressed in Day, no
problem.
How to deal with lag as ed or % ?

thanks in advance.

 

[John]

I'm using MSP2000
I'm trying to build a form to show all pred./succ for the selected task with
more detail information e.g. TF,FF,ES,EF,relation& lag, duration...
and the most important point is to highlight the driving pred./succ, just
like in P3

Now I have creat the form. using listbox to show the preds' detail
information.
But the problem is how to identify which pred. is the driving preds, Does
MSP has some build-in method to identify this, or any idea how to do this?

I'm trying to calculate the start date by using preds' start date,
relationship, lag, calendar, if the the date from my calculation is same as
the date from MSP then i consider this pred driving. is there any better
solution.

another problem is how to get the proper lag, for lag expressed in Day, no
problem.
How to deal with lag as ed or % ?

thanks in advance.

doniy,
Calculating dates might be one way to determine the driving task but I
tend to think it is more complex than necessary. Just off the top of my
head I think I would use the Total Slack field. Find which predecessor
task has the same Total Slack as the selected task - that should be the
driver.

As far as finding the lag, the VBA model for Project 2000 introduced a
TaskDependency Object. One of the properties of that Object is the Lag
Property. Look up the syntax in VBA help. And just for reference, most
time related objects in Project are expressed in minutes in Project's
underlying database. What you see in a view is simply a conversion for
display purposes. Therefore it doesn't really matter if the view shows
"days", "ed", or whatever, the value obtained by reading the object will
be in minutes.

Hope this helps.
John
Project MVP

 

[Jan De Messemaeker]

Hi,

Fellow MVP Jack Dahlgren developed a macro to do just that.
It's called Trace and can be found on his website:
www.masamiki.com

HTH

 

[doniy]

Hi Hohn,
Thanks for your reply.
That's a great idea to compare TF. I'll try it.
For Lag, I 've did some experiments to read Lag using dependency object.
you're right. "days", "ed" are in minutes.
but for lag as " 3SS+4800%" , the value of lag is 480, it seems the value is
4800%/10. the problem is I don't know how to interpret the value, 480 is 1
day or 4800%.
Maybe percentage Lag >100% is not a common use, so I can ingorn. For value
<=10, consider it as %, >10 consider it as minute. Am I right?

 

[doniy]

Hi Jan,
Thanks for you reply. I found a lot of useful micro there.
But the Trace is using Freeslack to identify driving or non-driving.
for tasks have multi-pred it may not work. e.g. task A have 2 preds P1 & P2
both have 0 free slack, but P2 has a succ. task B, it's B that make P2's free
slack 0, but not A.

 

[Jan De Messemaeker]

Hi,
I haven't looked at the code but it seemed to work for me.
If you are on the level of knowledge you are, why not change it yourself?
HH

 

[John]

Hi Hohn,
Thanks for your reply.
That's a great idea to compare TF. I'll try it.
For Lag, I 've did some experiments to read Lag using dependency object.
you're right. "days", "ed" are in minutes.
but for lag as " 3SS+4800%" , the value of lag is 480, it seems the value is
4800%/10. the problem is I don't know how to interpret the value, 480 is 1
day or 4800%.
Maybe percentage Lag >100% is not a common use, so I can ingorn. For value
<=10, consider it as %, >10 consider it as minute. Am I right?

doniy,
Generally I don't use lag on any tasks and on the rare occasion that I
do, I limit it to 30 days or less (based on schedules that span a year
or two). In my opinion if the lag is excessive, and 4800% certainly is
excessive, the link relationship isn't really valid. Either the task
should have an independent start or be linked to something more
appropriate.

Percentage used in a lag is relative to the duration of the predecessor
task. For example, if task 3 is 5 days duration and task 4 has a
predecessor of 3SS+100%, the start of task 4 will be 100% x 5 days or 5
working days after the start of task 3. If the lag is 4800%, then the
start of task 4 would be delayed 4800% x 5 days or 240 working days
after the start of task 3.

Hope this helps.
John
Project MVP