Feature request: An "evaluated at" graphic functionality

[PhilipOakley]

I was just doing an explanatory & investigatory worksheet on logistic regression and wanted to show

d/dx( p(x) ) "evaluated at" x=0 i.e. with a righthand vertical bar and x=0 at it's bottom right (commaa separated for multi-vars)

and realised I didn't think we had this symbolic / graphic capability.

So it would look like:

d/dx( p(x) ) |

|(X=0)

I certainly would like this type of capability, rather than having to show

d/dx( p(0) ...... which doesn't work!

or define a temporary function name (clutter) and evaluate that.

or ?? couldn't think of a short way using programming tools.

This (reverse order of presentation) can also be extended to the programming capability where we need implicit test cases such as 'evaluate for all i and j, except when i=j (i.e. 'i.NE.j')

[AlanStevens]

There is the 'substitute' option using the symbolic menu, though this is uglier.

Another option is:

though this is rather cumbersome, and perhaps runs up against your 'clutter' constraint.

Hmm! I support your request. What are the chances of getting it implemented do you think?

Alan

[PhilipOakley]

Neat idea, but like you say it's a bit cumbersome.

What is really needed is a 'graphic design' capability, so we can set out the 'graphic layout', indicating where the parameter substitutions go, and then we could have any fancy maths!

Mind you there are a few common layout styles that should be provided for mathcad to gain some new traction (I've been fighting a mainly loosing battle against Matlab!).

Philip

[AndyWesterman]

how about :

Regards

Andy

[AlanStevens]

A Westerman wrote:

how about :

Regards

Andy

The disadvantage of this form is that it only works where the d/dx(p(x)) can be evaluated symbolically, as the lim operator only works symbolically Although I used the symbolic arrow (because I'd been thinking about the symbolic 'substitute' form) it would have been more sensible for me to have used the standard numerical =, as my version then works even where dp(x)/dx can't be evaluated symbolically.

Alan

[ViktorKorobov]

We can also apply a combination Ctrl+Shift+J and Crtrl+Shift+K.

Viktor

[ValeryOchkov]

and about it: