## How to use MmaTranslator?...

Good morning Maple experts, When I use FromMma() to the following expression: Test1 := ( T = {1, 2, 3}; Clear[v]; v[{}] = 0; v[{1}] = 1; v[{2}] = 2; v[{3}] = 3; v[{1, 2}] = 4; v[{1, 3}] = 5; v[{2, 3}] = 6; v[T] = 19;) I got only Test1:=T:=[1,2,3] The function I used was FromMma(`Test1:=( T={1,2,3}; v[{}]=0; v[{1}]=1; v[{2}]=2;v[{3}]=3;v[{1,2}]=4;v[{1,3}]=5; v[{2,3}]=6; v[T]=19;)`); 1. Where is my mistake? 2. What are the equivalent expressions in MAPLE? .. How may I write it without using MmaTranslator? Many thanks for the help!

## Question On Tensors...

I apologize if the forum is strictly for undergrad students. I'm now on the section of Arfken's text "Mathematical Methods..." that deals with tensors, and I'm having a little trouble. My problem is how to physically or intuitively, picture (for lack of a better word) tensors. This also adds to the problem of not fully understanding and appreciating the difference between covariance and contravariance, other than it seeming to be arbitrarily subscripting or superscripting the tensor elements. Thanks, dc

## Hotw to get the data from a 3d plot...

How do I get the data from a 3d plot in maple 9 to a .txt or .dat file so I can plot it in origin or whatever?

## Saving...

When I click the "Save" or "Save as" options in my maple work, nothing happens, I can't save what so ever, does anyone else have this problem and if so, how do I fix it?

## Maple 11 Introductory Programming Guide...

On page 121 of the 2007 edition of the Maple 11 Introductory Programming Guide in section 3.6 Exercises, problem 3, it says: "... Find the inverse of (a*b)/c+((a-d)/(b*e))*I) in standard form, where a, b, c, d and e are real." Here is my failed attempt: View 4937_Problem_3.mw on MapleNet or Download 4937_Problem_3.mw
View file details TIA

## IntTutor doesn't show me the trick...

Hi, let's say i want the Integration Tutor show me how to integrate a function. Sometimes i don't know what the next step is, so i click the get-hint button. When it says "can you do a change of variables?" then i sometimes can't because i still have no idea. So i click "next step" and the result is shown. But i want to know what the substitution actually was, because it't not always obvious. But Maple doesn't tell me, for example, "t=2x has been applied" or similar. What to do ?

## How to format numbers and save memory?...

Hello Maple friends, I have a loop like this: A := array(1..10); for i from 1 to 10 do A[i]:= [ i, i^2, evalf(i^(1/3))]; end do; print(A); Nevertheless I dont know the following things: 1. How may I format in the way that in the third column of my array I see only 3 decimals? 2. As my matrix "A" is very big.. it is this the best way to avoid memory problems or there is some way to reduce this problem? Thanks in advance for any help! Jean

## local optimization with Optimization package vs. f...

Hello Maple community!

As a part of a more complex (global) optimization problem I have a simple trigonometric parametrization of a classical probability distribution, i.e. just a list of positive number that sum up to 1. For test purposes, I take now one arbitrary element, p, of that probability list and use it as a target function for an optimization. Of course, one expects that one will find suitable parameter sets for minimizing/maximizing p. So here is my simple target function for the case of N=10 probabilities (requiring N-1=9 parameters):

objective := proc(x1, x2, x3, x4, x5, x6, x7, x8, x9)

## Motion of airplane...

I have found a very interesting physics problem which describes the motion of an airplane, it is a very simple math model. We use only two coordinates, x(t) and y(t), t is the time. The airplane starts at the point (0,a), a>0 and airport located at the origin (0,0). It leads to the differential system ( v0, w>0 are given ):
```sys_ode:=diff(x(t),t)=-v*x(t)/sqrt(x(t)^2+y(t)^2), diff(y(t),t)=-v*y(t)/sqrt(x(t)^2+y(t)^2)+w;

d                v x(t)         d                v y(t)
--- x(t) = - --------------------, --- y(t) = - -------------------- + w
dt                         (1/2)   dt                         (1/2)
```

## Integrating erf(ln(x))...

I am currently working on a project that would involve students integrating a standard normal cumulative distribution function in Maple (essentially an erf function). This a simplified version of what we're attempting to integrate: CDF(a*ln(x)+b) from x=0..S. This should yield a closed-form solution like S*CDF(stuff)-K*CDF(other stuff) Of course, if one attempts to integrate the original CDF the integral will not evaluate. Is there a way around this, or will Maple simply fail to integrate erf(ln(x))? Thanks, Dan

## matrix spacing issues with low zoom factor...

Hi, I've been using maple10 worksheets under os x, setting the default zoom to 75%. This is fine. However, I've recently migrated to a linux system. Now, if I display a matrix under maple10 (or maple11) with 75% zoom, all of the spaces around the entries of the matrix are lost! This makes for unreadable 2d output. This is also true under 50% zoom (which is already unreadable) and if I change the default zoom in my .maple10rc file to _anything_ less than 100%, the same loss of spacing results. Does anyone else find this to be a problem. Sure, I can work with 100% zoom, but if there's a s

## Trying to plot two different functions...

The first function I am trying to plot with maple is r(t)=3cos(2t)i-2sin(2t)j, and the second is r(t)=(t)^(1/2)i+(t^2-2t)j. If anyone can help me with the command lines that I must type to properly plot these function in maple I would be very grateful. :)