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This specific constraint removes the free parameter of the previous implementation. This solves:
https://tracker.freecadweb.org/view.php?id=4501fixes#4501
However, this implementation of equal size produces zero gradients when coordinates of lines are aligned,
e.g. vertical or horizontal. These zero gradients, which are mathematically right ruin the diagnosis, which
regards corresponding elements as fully constraint (because they are locked from a solver point of view), when
they are simply locked, but are movable and constrainable. For this, when the rightful gradient is small enough
(<1e-10) it is substituted by a surrogate gradient of 1e-10, which solves the problem with the diagnose, which
treats as zero only values under 1e-13 (pivot threshold used in QR decomposition).
This special behaviour fixes the wrong detection here:
https://forum.freecadweb.org/viewtopic.php?f=8&t=53466&start=40#p464168
It also fixes this one:
https://forum.freecadweb.org/viewtopic.php?p=468585#p468587
A relative profile can now be used if it references itself. This fixes a compatibility issue with the V0.18 version of ArchRoof, where the first profile initially always references itself.
Make `Cell::setContent` use `unique_ptr` and
`make_unique` for expressions to avoid potential memory
leaks.
Also renames `expo` to `newExpr` to avoid mixup with the
member variable `expression`.
Both changes was made at the request of @chennes.
This commit only changes the user interaction with spreadsheet and does
not affect backwards compatibility (as valid cell expressions are
prefixed with '=' when serialized).
This fixes [#4156](https://tracker.freecadweb.org/view.php?id=4156),
which is discussed in the forum thread:
https://forum.freecadweb.org/viewtopic.php?f=3&t=39665
There has been additional logic added to handle numbers and simple
fractions without using '='.
The behaviour is what is expected by the spreadsheet test cases
and in line with how other spreadsheet software works.
The '-prefix can still be used to force the input to be handled as
as string instead.
Example of numbers and fractions handled are:
3
2mm
1/8
1mm/2
1/2mm
2/m
1mm/2s
More complex expressions are not handled without '=' and will be stored
as strings instead, for example:
2 / 3 / 2
1 + 1/3
- Previously a subtractive pipe on a body with no solids would create a solid. Now Pipe will generate an error.
- Fix incorrect property header. Previously Pipe was identifying itself as Pad (copy paste error)
