Hi, I need to calculate vector functions using cross-product, in Matcad looks like this:


I try to do the same in Smath using maxima but it doesn't work as I expect

Symbolic calculations are SMath's weakness.
You will see huge fractions for floats when symbolic optimization used.
Even when maxima or maple used, decimals shall be shown as fractions.
You can avoid this using eval() and round() to a certain point.
But it will not give result as mathcad or your desire.

Regards

There are several options:

• using custom units. Units are handled symbolically even in numeric evaluation by SMath. Disadvantage is that there may be clashes with pre-defined units. That is why I had to write 'u.0 instead of 'u.
  
• using Maxima as you did but with numeric evaluation in Maxima (using float()) and optimization=none in the context menu of the SMath region.
  
• if the symbolic part is just a factor, you can write it in the units field of the result and use numeric evaluation
  

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