## 1080 Reputation

15 years, 297 days

## Can't get proc on pg 62 to work as indic...

Maple
I wonder if someone could help me with the following situation. I copied the procedure 'differentiate' shown on p62 of the MAPLE10 Aadvanced Programming Manual. When I fed this proc w/ the parameters 2 - x + x^2 + 3*x^9,x as indicated on pg. 63 I did not get the result shown in the book. View 2292_P62 AdvancedProgrammingGuide.mw on MapleNet or Download 2292_P62 AdvancedProgrammingGuide.mw

## Square root problem again...

Maple
I have the equation (x+k)^2 = -d (7) I want to get (x+k) = sqrt(-d) by inputting sqrt(lhs((7))) = sqrt(rhs((7))) but I run into that old problem of sqrt(v^2) = sqrt(v^2) I realize you can use 'assuming' but its awkward and messy in this case. Perhaps the best way to present this question is to ask "What's the easiest way you can get from (7) to (x+k) = sqrt(-d) (8)

## WildCard in subs...

Maple
In a worksheet I have the following subs({tan(a)=sin(a)/cos(a),tan(b)=sin(b)/cos(b)}, eq1) The following doesn't work, but I was wondering if there was any wild card character that would enable me to do something like this subs(tan(?)=sin(?)/cos(?), eq1)

## Identity Matrix...

Maple
I have been trying to come up w/ a fast way to get identity Matrices which can later accept non-zero non-diagonal entries. If I use the shape=identity parameter then the Matrix can't be manipulated. This is what I've come up with KronDelt :=proc(i,j) => if i=j then 1 else 0 end if end proc: Matrix(1..4,1..4,(i,j) -> KronDelt(i,j)) Was it necessary to seperately define KronDelt ? I tried putting a mapping directly into the Matrix constructor but always got a syntax error, e. g., Matrix(1..4,1..4,(i,j)-> if i=j then 1 else 0 end if ) This doesn't work. Is there any way to d

## Slow numerical entry...

Maple
On a whim I decided to write a routine to numerically calculate the volume of a sphere and compare the result with the well known formula (4/3)*Pi*r^3. What struck me was how slow the MAPLE code ran compared to the same code in VB. I realize that a program like MAPLE which is geared toward symbolic mathematics would not be expected to be as fast at numerical calculation as other vehicles, but I was struck by the difference. Below is the code in VB and MAPLE. Both routines give the same answer. The MAPLE roputine runs about 10 times slower than the VB routine. I was wondering - perhaps I'm not being fair to MAPLE. Is there some way I could have written the code to run significantly faster?
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