MathCAD and clones

[ahbushnell]

I hope this is the correct location for this.

I have used MathCAD for many years and think it's great.  This software shows math like it would be in a published document but acts as an engineering spread sheet.  And one of the most important features is it keeps track of units which has saved me many mistakes. 

The downside is PTC bought MathCAD.  I purchased the MathCAD Prime 5.0 and use it.  But it was expensive and I pay support.  The down side is the support is not very responsive. 

I'm looking for a clone.  I'm not looking for Matlab or something like that.  I like Matlab and use it but it does not keep track of units. 

Any suggestions?

Andy

[Neilm]

I have tried SMath - seemed reasonable. I did use it a while ago so I don't know how good the later versions are.