Calculations and formulas in Schedules

[Erik Bjornhage]

So, this is perhaps a bump from previous topics but the full functionality has not yet been solved.

My wish is for spreadsheet style calculations in Schedules.

As a simple example:

A big residential project - with a number of different apartment types (1 bed, 2 bed, 3 bed etc.) which is of course a part of a total number of apartments. Currently we cannot list these apartments and have the schedule display their repective percentages in relation to the total. This would be extremely beneficial to general project management and how and what we can deliver to clients.

[Erik Bjornhage]

@Francois_MCD - I wish that was true, but sadly no.

You can get a lot of information and a lot of calculations done through expressions but there are limitations.

To follow the previous example, yes you can easily distinguish between 1Bed, 2Bed etc. and calculate their individual numbers.

However, you cannot get the schedule to display their percentage of the total number of apartments - something which is crucial.

[Nader]

 @Erik Bjornhage  send me an example project and I may find a solution

[Gonzalo]

Hi @Nader

First, I'd like to express my interest in this topic and thank you for your time. For example, one can use formulas with properties to calculate the cost of building a brick wall, but if you want to calculate the cost of earthworks, for instance, you would need to have both elements — the cost calculation for brick walls and for earthworks — to later sum them up by referencing both properties.

On the other hand, if I want to calculate the percentage of something over a total, as Erik mentioned, I would need to create a property, maybe in the project information, that is a static number representing the total. This way, I could divide later on. For example, if I want the number of bedrooms in a house, I could sum the areas classified as bedrooms by assigning a property where a bedroom-type area equals 1, and a non-bedroom equals 0. I could then sum this and create another property to calculate the total area of all zones and divide the total number of bedrooms by the total area.

However, applying this to each zone — since every element can have a property but you cannot have a "global property" associated with the entire project and not just an element — makes this complex. Maybe it is possible, but it is not as simple as Excel where you can just add a row with the total and then divide it by the sum in the next column, and you’re done.

Something that could be very simple and useful would be the ability to perform basic arithmetic operations with sums or results from the schedules, whether they are total or individual quantities. Perhaps I’m getting tangled up, but does this make sense?

P.S. I managed to solve this by creating elements as objects placed on a hidden layer, assigning a property to those objects, and then using them as constants. However, it's a rather convoluted workaround for something that should be much simpler.

[Erik Bjornhage]

@Gonzalo 
That's certainly a work around - but I can see that as a working solution when you have deadlines and stress this work flow would break down quickly. There is another wish regarding Area Calculations in Schedules that tie in with this and there are other use cases where the need for proper spread sheet style formulas are sorely needed.

[Pato99]

I use expressions to do this.

But I'm voting for you because I want you to reach 200 votes!

[Erik Bjornhage]

@Pato99 
How do you use expressions do achieve this?
Can you give some concrete examples of how you set up your formula?

[Pato99]

It's similar to as @Gonzalo mentions above. 

I schedule all similar properties eg Zone Name = Bed and Zone Number = 1 or however it is you go about it, get the Sum of each then plot these into a custom GDL object with expression-based properties. Then schedule the object.

There is the manual task of updating the object parameters but if you have everything else scheduled it's easy to turn on trace and punch in the numbers it takes about 10 seconds at the end of a job.

I would much prefer the development time be spent on allowing expressions to use data from other sources or allow a property type to reference a specific item and be used as a global variable, this would solve your problem and also allow it to be used throughout the project and not just in schedules. But beggars can't be choosers.

[Erik Bjornhage]

OK, yes - similar to @Gonzalo and still involves a manual aspect when it comes to updating.

The manual aspect is the one I want to eliminate. I need for the schedule to be so automatic that anyone can open my file, update a specific layout and then publish it - without any manual editing of properties. When you're dealing with a project of say 400 or so apartments and have limited time - then it doesn't take ten seconds at the end of a job.

What if we start to automate the publishing process - the automation process cannot know which parts of the schedules and/or deliveries need manual editing to be correct.  Which in turn means that the end result is incorrect. The repercussions if your numbers are off can be fairly significant...and this is something that we are expected to keep delivering and keep updated on a fortnightly basis (sometimes weekly).

Again, I know that there are workarounds - but this is 2024 and something as simple as this should not need workarounds. 

[Pato99]

I agree, for a BIM program this shouldn't even need to be a wish. I just don't want to see them get carried away with adding functionality to the schedule, that doesn't extend beyond schedules.

EG. They add the functionality to create a sum or percentage [between two different elements] in the schedule but then we can't use that value in auto text, labels or as a parameter for an object. 

They put a lot of effort into formatting the schedule style last year but did nothing for functionality. Like anything, function before form. 

[Mats Knutsson]

Simple stuff we'd like to do with schedules...summarizing kg CO2 per design options filtered on for example classification. I totally agree with Pato. These wishes shouldn't even be wishes. Lame...