Anomolous behavior in property box

[openBrain]

Indeed. It seems to appear when dimension has inch decimals.

in which units schema are you talking about?

In "Building US". I didn't duplicate elsordo's work that found it to be the only mode in which it appears.

[elsordo]

Has a ticket been created? If not, should I do it?

I find the bug to be most annoying. If I want to work with numbers in the property pages, I have to change units.

-David

[Geoplace]

Yes its the same behavior as this post.

https://forum.freecadweb.org/viewtopic.php?f=3&t=35401

It seems that when input mixed units must be clarified if we need to format the input as:
1) Human readable format -1ft10in (All are expected negatives)
2) Algebraic expression format. (-1ft-10in)
3) Force to use the formula editor. (when two units detected in the field)

Formula editor.PNG (4.31 KiB) Viewed 719 times

It doesn't matter if you combine feet /inches or
meters /centimeters.

The negative number are a general behavior even in new file.
-1'10" = -50.8mm insted of 558.8mm you need to input -1'-10" to get what a human expect.
-1m50cm = 50cm insted of -150cm you need to input -1m-50cm to get what a human expect.

It could be a new feature request for error proof data input.

[metatheorem]

I've opened a bug for this issue: https://www.freecadweb.org/tracker/view.php?id=3925.

[jmaustpc]

Has a ticket been created? If not, should I do it?

I find the bug to be most annoying. If I want to work with numbers in the property pages, I have to change units.

-David

Hi David
after a lot of time, I completely failed to recreate your issue in a file other than your example posted. Thank you for posting the sample file as without it I would never have worked out what was happening since I could not re-create the issue here. until I realised that you had a negative number in the property.

The problem is not what I interpreted your report as describing at first, the problem is actually the way more complex multi unit input is effected by a negative value.

Has a ticket been created? If not, should I do it?

As far as I know there was not ticket created for your specific topic, however to be clear the ticket needs to address the issue of how negative number are handled with complex multi/unit input.

Yes its the same behavior as this post.

Could one of you two please create a bug report ticket to address the issue of how negative number are handled with complex multi/unit input? Please put a link in the tick to both topics and a link to the bug ticket in both topics. If you have any trouble with any of that, please let us know so we/I will fix it.

However in the mean time, it is considered by some at least that using negative numbers is bad practice. At the very least it can lead to complications in more complex scenarios. For example, if/when you try to extract material quantities data from your model, you have to be very careful to ensure that a negative value somewhere does not create a value of material such that when a total length or volume is calculated, it does not subtract from the total rather than add to it.

I have designed several houses with FreeCAD including a real one that was used in official documents for a building permission application. Personally I used Sketcher for the geometry base objects rather than Draft objects due to their power and parametric abilities. FreeCAD has advanced enormously since my first house model. With a little care and forethought sketcher and Draft can easily allow you to work without negative values, however sketcher does have some advantages with avoiding negative values.

With something as complex as a house, I found creating a spreadsheet to store various values (e.g. internal and external wall thicknesses, overall house slab dimensions, etc.) and then referencing those with expressions in sketcher constraints and other areas was a good idea. It takes longer at first, but it allows easily changing of values and dramatically removes the chances of finding the "topological naming limitation", hence made my model infinitely more robust and adjustable.

my version data.

OS: Kubuntu 18.04.2 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.
Build type: Release
Python version: 2.7.15rc1
Qt version: 5.9.5
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/Australia (en_AU)

[jmaustpc]

I've opened a bug for this issue: https://www.freecadweb.org/tracker/view.php?id=3925.

Thank you for that. You posted at the same time as me.

[Shadow]

Issue is now located at https://github.com/FreeCAD/FreeCAD/issues/5909

I have commented how this bug manifests in 0.21-devel