In brief, SolveSpace's solver could be hacked to kind of support inequalities, but it was never made for that. Some earlier threads:

http://solvespace.com/forum.pl?action=viewthread&parent=211
http://solvespace.com/forum.pl?action=viewthread&parent=886

Also, some time its needed prevent to change vector (for example, "line could be enlarged only from start point in left direction, and not in reverse")

@jwesthues, This actually was made and works fine. I even don't see any "hacks" in this solution, just the pure mathematics :)

Are they any plans to bring this into the core? I would love this feature.

No immediate plans, other tasks have a higher priority.

This actually was made and works fine. I even don't see any "hacks" in this solution, just the pure mathematics :)

@jwesthues & @Evil-Spirit, so if it work in test, why not implemented yet?

@jwesthues,
@whitequark,
@Symbian9,
Uff... I made it!
Evil-Spirit@6b7e99b

case Op::NORM: return a->PartialWrt(p)->Times(a->Abs()->Sgn());

This actually was made and works fine. I even don't see any "hacks" in this solution, just the pure mathematics :)

I even don't see any "hacks"

"hacks"

Uff... I made it!

Evil-Spirit@6b7e99b

Evil-Spirit, you are the man! Do not forget call @probonopd to this party too!

Can you please merge this? Looks very nice!

KmolYuan/python-solvespace#3

Yeah, it's in my review queue. I did not forget about this patch though.

BTW if we could just enter the inequality or range like this, it would be smooth:

(it already supports some kind of basic math like subtraction, so this can be nice addition)