## mindless numerical recursion

by: Maple

Ref: Kahan (Jan 2007): How Futile are Mindless Assessments of Roundoff in Floating-Point Computation ?

I wanted to know, how Maple behaves on the example given in \2475 of that working paper (where other

systems are considered, mostly Matlab) and thought it might be of interest here in the forum.

> restart; Digits:=16; interface(version);

## Bug in 'limit' ?

by: Maple
```( 1+ c*10^(n+1) ) / ( 1+ c*10^(n) ): 'limit(%,n=infinity)': '%'=%;

(n + 1)
1 + c 10
lim       --------------- = 10
n -> infinity             n
1 + c 10

However if c = 0 then ...
```

## How can I add blank spaces?...

How can I add blank spaces after each comma in the following so that the output will be easier to read? print(X_bar[1] = Mean_SampleMeans1, S[1]^2 = Var_SampleMeans1, S[1] = SD_SampleMeans1); X_bar[1] = 5.993500000, S[1]^2 = 5.102310060, S[1] = 2.258829356 I am using Maple 10 worksheet mode (Mac). Maple ignores any additional spaces after commas in the input. Thanks for your help. Thomas

## How to redefine standard operators...

Hello, is there a way to give new properties to built-in operators, such as `+` or `*`? For example, I have my own type MYTYPE and procedure for adding MyAdd(a::MYTYPE, b::MYTYPE). Now, I would like to use: a + b instead of MyAdd(a,b). Is it possible? Thank you. Karel

## Mathematical Expression Component is different...

by: Maple

Hello, I have a question about Mathematical Expression Component in document. I tried to use it in my maple document and of course I looked at the help about it. There is a discription about another component, I think. The reason of it is that the dialog of component property is different in a help and in a document. I do not know why. I try to use it in Maple 10.06. The following figures show the situation. Of course, problem of this component is not only in different property dialog but also in functionality. Figure from help Figure from document Problem with this component is described also in the document here. Thank you. Vladimir

## Linear Algebra...

I seem to be having some trouble with scalar multiplication. Perhaps you all can help out. Here is what I have; with(LinearAlgebra): A:= matrix(3,3,[1,2,3,4,5,6,7,8,9]); ScalarMultiply(A,3); I was hoping that would work, but after the ScalarMultiply command I get "Error, (in LinearAlgebra:-ScalarMultiply) expects its 1st argument, MV, to be of type {Matrix,Vector}, but received A" Any ideas where I am going wrong? Thanks in advance.

## want delta x as a variable...

Probably me doing something wrong but just wanted to know.... I wanted to assign a value to a variable... delta x but I wanted to use the greek delta with the x. (e.g. Δx) Maple doen't like it, and flags the error. Error, first argument to _Inert_ASSIGN must be assignable I know it is only cosmetic but I just wanted know if its possible. Thanks, dgiznya

How do I find the numeric value of these equation.I want actual value of all symbols( alpha,beta and gamma) 1) b_2 = -3.464909430*RootOf(-gamma^2+alpha*beta+(-gamma^2-4*alpha*beta)*_Z+(gamma^2+4*alpha*beta)*_Z^2, label = _L1)+1.732454715 2) b_1 = RootOf(-gamma^2+alpha*beta+(-gamma^2-4*alpha*beta)*_Z+(gamma^2+4*alpha*beta)*_Z^2, label = _L1)/alpha 3) Z = -.5772156649*alpha/(2.*RootOf(-gamma^2+alpha*beta+(-gamma^2-4*alpha*beta)*_Z+(gamma^2+4*alpha*beta)*_Z^2, label = _L1)-1.)

Please help me find the numeric values of a_1,a_2,b_1 and b_2, base on the below equation. solve({a_1^2*alpha+a_2^2*beta=a_1,2*a_1*a_2*alpha+a_2^2*gamma=a_2,a_1*b_1*alpha+a_2*b_2*beta=b_1,a_1*b_2*alpha+a_2*b_1*alpha+a_2*b_2*gamma=b_2,b_1^2*alpha+b_2^2*beta=a_1+b_1,2*b_1*b_2*alpha+b_2^2*gamma=a_2+b_2,a_1*b_2<>b_1*a_2},[a_1,a_2,b_1,b_2]);

## Problems Ploting with DEplot...

I'm new to Maple and just starting a ODE class. I attempted to do a Directional Field plot using DEplot. The plot displayed only Q3 and no mater what I tried would not plot the other quadrants. My inputs: with(DEtools): desgn := diff(y(x),x)=-x/y DEplot(desgn,y(x),x=-10…10,y=-10…10); Seems simple enough is there something I’m missing? I tried to change the range by the right click over the plot; did nothing. Sorry if this is overly simple but, I’m still learning… Thanks for any help anyone can offer.

## ImageTools and LinearAlgebra packages...

I am teaching a course on wavelets. I have two items that are giving me trouble with using Maple 10. 1. I read a JPEG image into my worksheet, and then I want to multiply it by a filter matrix. I get an error because the filter is a Matrix and the image is an Array. How do I fix this problem? 2. Once I have changed the image, I want to see the result. The only way I have found to do it is to save the resulting array to the hard drive, and then use the Insert tab, and choose image. There has to be a way to do this without having to store the Array. How? Bo Green

## Improper integral trouble...

View file details. Am I making a silly mistake here or is Maple incorrect? Lance N.