Program help needed

[DrD]

1. ... "However, your post suggests you did this in the CAS view" ....

I used the same CAS view example: grad(x^2-3*x*y^3,{x,y})); throughout this thread. It is from that, the [vector] [-3*y^3+2*x -9*x*y^2] appears. The y-component, -9xy^2, is from the virtual calc, (not me), and looks like a (smaller) negation symbol, to me. All of the expressions used in this thread were from cut/paste activities. Without comma separation, the visual appearance looks like a single expression! (It acts normally though).

[Textbook Display checked]
Enter this: subst([-3*y^3+2*x, -9*x*y^2],{x = 1,y = 2});
The vector's comma disappears, replaced by a space, the vector suddenly looks like a single expression.

Displays this: subst([-3*y^3+2*x -9*x*y^2],{x = 1,y = 2}) ===> [-22 -36]


2. ... "I suspect that when you typed: mat2list( [-3*y^3+2*x -9*x*y^2] ) you used the subtraction key and not the negation key. So that leads me to a question, the answer to which I am most curious:
Did you create the vector [-3*y^3+2*x -9*x*y^2] in Textbook Entry mode? And if so, did you use the comma button to create the space or did you use the space key?" ...

Maybe the sign was changed along the way {unintentionally}, not by my hand directly. IF you see comma separations then Textbook Display was unchecked. IF you see space separations, Textbook Display was checked. Cut/pasting is how the vector was entered in CAS view. With positive vector components only, the display still behaves similarly, of course, but the space separator becomes more obvious.

To conclude this thread:
Unchecking "Textbook Display" thus using comma separators, makes visually displayed results more legible. Using comma separated vectors is likely to be less error prone for students (especially in my case).
Double quoting CAS command expressions and variables makes them functional in HOME view, or ppl programs.

Thanks, Han. I do appreciate, very much, all the informative help you've provided. It sure would be helpful if HP would spend a dime on improving documentation, and let the hardware and software rest awhile.

-Dale-