opus64

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2 years, 259 days

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These are questions asked by opus64

Hello,

I realize that I can use solve to isolate a specific expression. However, often I have a complicated equation and I want to move 2 or more variables to one side, not knowing a-priori what the expression is going to look like. Is there a way to do this? It almost seems like I have to do work by hand to figure out what expression to pass to solve in this case.

It could be that I'm following the wrong workflow, but I often want to do this, move variables to one side as best as I can, and then look at what expression I endup with to make other decisions about how to solve the problem(computationally, etc).

Thanks.

Hello Maple friends,

I use Explore() often and noticed something today which seems like either a bug or an error on my usage.

I have a long worksheet where I use Explore at one point to show the behavior of an expression relative to one parameter assigned to a slider. Later in the sheet however, I re-assign some of the variables used in that expression and I call Explore again to see how the expression behaves with the different parameters.

The issue is that when I move the slider on the first explore, the result is incorrect because it seems to be using the values of the variables at the end of the worksheet, not the variables at the point the Explore statement exists.

I would expect Explore to make a copy of the stack at the point it gets called such that the result is correct in the context of its location in the worksheet.

Is this the correct behavior and is there a way to make this work as expected? The only workaround I have in mind is to rename the variable names just to make Explore work, which doesn't seem like a great solution.

Thanks.

Hello,

I'm sure this is a dumb question, can someone remind my why this doesn't work and how to get around it?
 

restart

with(VectorCalculus)

V := `<,>`(A, B, C)

Vector[column](%id = 18446745896443115750)

(1)

A := 1

1

(2)

"(V) ? ()"

Vector[column](%id = 18446745896443115750)

(3)

``


 

Download VectorCalculusQuestion.mw

 

 

Hello,

All too often I encounter an annoying issue, and when it happens it makes Maple slower than just scribbling on paper.  Unfortunately I don't understand why it happens or when it is going to happen so it creates a huge waste of time.

While most of the time expressions behave as expected, other times the exact same expression behaves as if it is something other than what is shown on screen.  I just ran into such an issue as an example:

What am I missing here? Why would phi not be interpreted as phi?

The only thing I could think of not being a Maple expert is assumptions.  I found I have an assumption earlier on phi (assume(phi>0,phi<45) so I removed it, but inexplicably(to me) that only fixes the first 2 lines, the last 2 lines still have the same issue, why I can't understand.  Why would having an assumption on phi, prevent me from evaluating the expression at some value of phi? The provided value is even within the assumed range.  And in either case, why can't I declare a value for phi and have that be understood?

Sorry for what I suspect is a dumb question, and thanks in advance.

EDITED to correct = -> :=

I'm using variable names that have subscripts, not as a table index but literal i.e. R__1 as a unique variable name.  It seems whenever I make assumptions on variables that have subscripts, when I use them the variables that have subscripts are printed twice:

 

Can anyone explain why this happens and how to get around it?

 

Thanks in advance.

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