## Duplicates on lists....

Hi Hope anyone can help. When using this syntax in Maple 10: >restart:_EnvAllSolutions:=true: f:=(x,y)->x^3*y-2*x^2*y+x*y^3; GRAD:=[diff(f(x,y),x),diff(f(x,y),y)]; STATS:=solve(GRAD,[x,y]); I get the following output: 3 2 3 f := (x, y) -> x y - 2 x y + x y 2 3 3 2 2 GRAD := [3 x y - 4 x y + y , x - 2 x + 3 x y ] STATS := [[x = 2, y = 0], [x = 0, y = 0], [x = 0, y = 0], 2 [x = 5/4, y = 1/4 RootOf(_Z - 5, label = _L2)]]

## Tablet PC Operation

by: Maple
Hello, I have tried to run the Maple 10 program on my Toshiba Tecra M4 TabletPC and it runs fine until I go to Tablet Mode. The only part of the program that will run in Tablet mode is the Classic Worksheet. The symptoms are that the windows that appear in say the documentation mode (in Tablet Mode) come up but are solid gray. The program seems to hang. Now what I mean by "Tablet Mode" is that you flip the touchscreen around and lock it on top of the keyboard. This cause the display to go from a horizontal presentation to a vertical sheet of paper presentation. Regards, Dave

## How do I make 3D surface plot from Matrix?...

Hi, How to make surface plot from elements stored in matrix of form [x,y,z]? Let's suppose I have the following matrix: >A:=matrix([[1.00, 1.00, 167.76], [1.00, 2.00, 95.588], [2.00, 1.00, 500.64], [2.00, 2.00, 335.51]]); The first argument from the lists is value for X axis, the second argument is value for Y axis and the third argument is value for Z axis. For example: x=1, y=1, z=167.76 x=1, y=2, z=95.588 x=2, y=1, z=500.64 x=2, y=2, z=335.51 How to make such plot in 3D?

## Maple's 3 Valued Logical System...

Is Maple 10's logical system called a three valued one simply because of the value FAIL, in addition to the truth values true and false ?

## Superscripts in Linux...

I've already bothered two other forums with this (retarded?) question, but I'm not getting any answers. So I'm bothering you now. I apologize. I tried to search but didn't find anything. The problem is I'm not able to type ^ or input superscripts in Maple 10.02. I'm using FVWM2, but the problem occurs in KDE, too. Maple clearly gets some input, but is it not visible, and it doesn't have the same effects as a caret does. Maple displays letters with carets like ô fine, but not the caret alone, nor does Maple indicate I'm writing a superscript. And I can type anything, but the first character after inputting a caret doesn't get shown, and I get no superscripts. For example, typing "x^22" is "x2" on the screen. While Maple clearly indicates that I'm about to write a subscript if I've entered an underscore.

## Getting infinite symbol in Maplet...

Does anyone know how to display "infinity symbol" in Label element in Maplet?

## Matrix of Differential operators...

Hi, I am trying to do define a matrix of differential operators for e.g |diff((),x) , 0 | | 0 , diff((),y)| |diff((),y) , 0 | | 0 , diff((),x)| once this 4x2 operator is defined i can apply it to any function of two variables f(x,y) or a compatible(in size) matrix of such functions. How can I define such an operator in maple? Thanks, saurabh

## Loop over complex calculations without memory blow...

Hi Maple'primes. I have a question that I am sure has been posted many times but I will do again. I am using Maple 10 and I am trying to sweep over a parameter space with a for loop. At each iteration of the loop I am performing a complex calculation : double/triple integral or solving a boundary value problem. If I compute the compuation as a stand alone execution then it take ~ 30 sec, however, when I loop through 200 iterations the loop never finishes and Maple tells me I am out of memory. When I look at the memory (bottom right hand corner) it keep increasing to crazy levels (Gigs) during the loop, when each computaion should be about 20M. It seems like Maple keeps track of all the old computations when I clearly don't want it to. How can I speed this up?

## Execution and UI components...

Hi, I have a matrix containing data read from an external file. I would like the user to select a colon number using a List box and, based on this number, build the resulting vector from the matrix. Is it possible to ask Maple to evaluate some parts (execution groups?) of a worksheet with some command (not menus)? Thanks.

## Creation of a simple datafile...

How do I generate a datafile (ascii-type) for the following general case: y1:=f1(x); y2:=f2(x); ... ym:=fm(x); so that the first column will contain selected values of x from x0 to xN, the second column will contain the corresponding f1(x0..xN), the third f2(x0..xN) etc.? Thanks, Miran

## Strange results of a numerical integration...

I try to calculate a numberical integration in 2 layer for loops(outer 21 times, inner 128 times): evalf(int(erfc(sqrt(B*xgms1*x/(x*xgmi1+xgmn1)))/gamav*exp(-1*x/gamav),x=0..infinity)), i.e., the kenerl is erfc(ax/(cx+d))×exp(-ax). But when "gamav" > 100000, the calculation time is too long to bear. So I try to do some approximation and change the upper bound into 10*gamav, 30*gamav, 50*gamav and 100*gamav. But I got the following results: BER1a1[18]=0.0001004773804, BER1a2[18]=0.0000365034983, BER1a3[18]=0.0000000096250, BER1a4[18]=0.0000000000001. The trend of results is bigger the upper bound smaller the results. Obviously, the results is wrong. When "gamav" is a smaller number, such as 1000, the four integration results is the same as when the upper bound is "infinity".

## Evaluating polynomials without knowing variables?...

Hello! I would like to do something that I really think should be simple. Suppose I have a polynomial P := x^2 + y If I want to evaluate it at the point [1,2], I could say: eval(x=1,y=2,P); But suppose that I didn't know the form the variables in the polynomial would take. Or suppose that I knew they were of the form x1,x2,x3,...,xn. Given a vector of size n, how can I evaluate my polynomial at that point? Thanks! Susan

## vector length in Maple 10.0 Classic worksheet...

Hi. Anyone knows a command on how to calculate the norm (length) of a vector? For example: Maple input: START >restart:with(linalg):#I know this package is obsolete, but my Teach only teaches theese commands.. >u:=vector([1,1,1,1]);#a vector i defined >LengthU:=sqrt(u[1]^2+u[2]^2+u[3]^2+u[4]^2);#This is how I calculate the length theese days... END Anybody knows a command, so that my third line will not be neccesary? TIA