• Remaining Lag = Lag - Elapsed Lag.
  • Lag is an input value.
  • Elapsed Time Lag is a function of dates. With the dates I can figure out Remaining Time Lag. This is available data.
  • Elapsed Volume Lag is an update value. This is available data.
  • The calculations can be tricky, better if done by the software.  Definitively it will be a welcomed value.
  • To edit Remaining Lag by editing Lag can be tricky, better if done by direct user input.
• I still wonder how you would deal with remaining lag2 on double links as lag2 can be tricky even if lag1 and lag2 are time lags.
• Same as activities Lags have associated dates for a lapse of time.
• Given the value for Remaining Volume Lag I am still concerned of current calculated end date for it to elapse.
• With the dates I can figure out Relationship Slack, the available reserve before it becomes driving.
• The calculations can be tricky as we will have to deal with dates for successor node, better if done by the software.
• I still wonder how you would deal with Relationship Slack when the relationship is a double link or when lag is a Volume Lag.
• To communicate with the field, dates can be easier to understand. For them looking at early vs late bars/dates is easier to understand than just giving early dates and float values, easier than just looking at activity start as a start milestone + remaining duration.
• The same goes with remaining lag, we know remaining lag starts at DD (unless there is out-of-sequence progress) but end date is of concern.  If you only give me remaining lag I still must figure it out to know when it is scheduled to end.  If you only give me relationship slack I still must figure out to know how late it can be delayed. To communicate remaining waiting time rather than saying 5 days under calendar C is easier if you spell the date.
• What Ron Winter is asking might be easy for time lags but not for volume and double lags.
• The more functionality, the harder it can get, it still helps if the software gives you the discarded dates.

I am trying to figure out how to calculate finish dates for volume lag without having to mimic volume lag as an activity of production type. 

• It looks like not all lag can be modeled as an activity, in particular volume lag.

In the following scenario I opened some SS and FF slack by delaying Cement Plaster using a date constraint.

Multiple resources working on different shifts, variable quantity and partial workloads can complicate the calculations that anyway were done during the schedule run.  In order to better understand current status and the schedule behavior these values are needed. 

Double lags I rarely use but volume lag I use more frequently.

Once I get those missing/discarded dates relevant to float such as start/finish Flex and lag finish dates everything will become clear.  I recall Ron Winter asking for those dates including the ability to indicate actual remaining lag.

• Making CPM More Transparent
• In-Progress Lag Report and Value  -   Remaining Lag should be displayed just as remaining duration is shown and editable.  The CPM feature of Remaining Duration was added so that Schedulers could monitor and change this calculated duration result.  Lags are to relationships what durations are to activities.  Why should Remaining Lag calculations be discarded by the software instead of saved and displayed?  Why should we be unable to indicate that actual remaining lag is only 2 days instead of the calculated 4 days?  Part of the reason CPM Schedules are so hard to understand is that fact that not all of the data used is displayed.

Any help will be welcomed.

Best Regards,

Rafael

Vladimir,

Basic Scripts to increase D1 by work hours done: 1st version missing ability for unit in days.  I used an iteration method as considering calendar week and exceptions by other means can be difficult.

N can be negative.

• A huge limitation of this approach is that the script can only be applied to a single date field.
• Another limitation is that N shall be an integer.  Maybe some sort of data validation for numeric fields could be implementd to limit values to be fractional/integer and to be within certain values range.
• A Spider Function is better for this purpose.

Best Regards,
Rafael

Excellent!

I already copied your last posting into a PDF for future reference, so good I suggest publishing it at Spider website and keeping it updated as need be.

Spider - Start, Finish and Float Fields

Best Regards,

Rafael

Vladimir,

As always thanks a lot. 

With the new menu option "View" it is easier to navigate to views like WBS Chart, Time Location Chart, Cost Components and many others, even when we already had access from the Tool Bar and Main Window.  I will mostly use new menu option but at times will continue using the other options.  Depending on what I am doing I will customize the Tool Bar for easier access to some views but will be able to access directly other windows from the new View menu without having to go to Main Window.  Needless to say Main Window is still invaluable to navigate among opened projects as well as opened documents, impossible to stop using it for some navigation needs.

About the view of basic double lag information on the Predecessors/Successors column at Gantt it is as expected but not sure if it is new or if it was already available.  Impossible to see all link parameters within these columns but it do help.  I just added 28 link user defined field easily visible at the links table, impossible to show them all at a single column.  There is no substitute to the links table view.

I cannot live without the Standard Reference Books functionality that makes easy the transfering of the UDFs, Formulas and Scripts to any other project.  I use codes with an added prefix for the items I will transfer among several jobs to make sure there will be no duplicate or conflict.  This coding add some clues about what the field means when you look at the formulas.

The new formula will be of much help to get the values at a single click rather than manually calculating the values for every line on the links table.  I suspect a few Spider Project users must be already doing some calculations impossible or impractical without these formulas and scripts and hope this new formula will be of help.  It looks like users will be able to explore exotic float and link calculations.

• Do not forget I am looking for start of Start FLEX as an available field, while shown in Gantt image as a narrow bar the date is not visible to the user.
• 
• As well as Finish of Finish FLEX it might be calculated by formula but I believe both shall be available fields.

Best Regards,
Rafael

• I have Date1, Diff_Days_Calen and Calendar Code. I am looking for a formula that will yield Date2 given the other values I know.  I am looking for a formula that will change a date by the difference in days/hours by calendar.
• BTW I am figuring out some tricks on the use of formulas and script editing that are making it easier to handle multiple If statements by calculating several formulas in sequential order.  Formulas in combination to scripts are very powerful; some calculations are impractical to do without the script.

Best Regards,

Rafael

How can I change a date by Diff_Days_Calen?

Double lags are visible in the Predecessors/Successors column I wonder if double lags were visible long ago because otherwise it would be too soon! Sorry for any inconvenience.

This is what I was looking for, I can look for lag calendars and any other link parameter at the links table.

Thanks.

• I am having issues to differentiate Start[Early] and Start fields.
• I am looking for ES if Interruptible [Start of Start FLEX].

It also came out the logic for the script can be complicated and that some logic commands would help.  For simple time lag formulas are easy, it gets complicated when you add double links and volume lags.