## 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restart:with(linalg):#I know this package is obsolete, but my Teach only teaches theese commands..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

## MATLAB coding...

Hello members, My question is out of maple primes, but i was wondering if one of the members is and expert in MATLAB coding. I am trying to write a MATLAB code for numerical integration for a double exponential equation of the form i = io(exp(-alpha*t)-exp(-beta*t). The problem i am facing is how to eliminitate the error as the integration is taken as the area under the curve, say from time t=0.0 to t=25e-6. Your comments in how to solve this problem is highly appreciated. Regards, JacquieD.

## Maple 10 and 64bit Linux, part 2

by: Maple

Many Maple users have a preference of user interface, whether it be command line (TTY), Standard (Worksheet or Document mode), or Classic. My personal view is that each may be suited for different types of task. While it's understood that Maplesoft is dedicated to supporting the Standard interface, I understand that some users remain devoted to the Classic interface.

I often use Maple 10 on a 64bit Linux machine, on which the performance of the 64bit Maple 10 kernel is comparatively faster for some types of computation. I discussed this briefly in an earlier post. But there is no officially released 64bit Linux port of the Classic interface. So below I'll mention an unofficial and unsupported way to use the 64bit Linux Maple kernel with the 32bit Linux Maple Classic interface.

## How do I can to develop a meteorology model with M...

Hello, I'm sorry for my poor English, my name is Arnaud, I'm 17 years old junior in a School (Laurent de Lavoisier) in France. I have a probem, I'd like to develop a program for meteorology modelisation with Maple. How could you do it? Thank you in advance. MOTZ Arnaud

## Default settings for sketches...

Is it possible to change and save the default background color and pen settings for a sketch?

## printing result into table form...

HIIIIIIIIIIIIIII! :) I'm doin a problem on the restricted 3 body problem...What i want is to creat a proc "equilibria(mu)" which finds all five equilibria of (DE) when mu_1=mu and displays, in a neat table, the (x,y)-position of each equilibrium and the eigenvalues of the vector field's Jacobian at that equilibrium. In addition, the table should indicate if the equilibrium is hyperbolic (all eigenvalues are real and non-zero), elliptic (all eigenvalues are imaginary and non-zero), hyperbolic-elliptic (a mixture of non-zero real and imaginary eigenvalues), or otherwise.. Now the difficulty is this, i can find the equ's and get the evalues, but i have a proble with gettin them into a table...i've been told that prinf is a good one to use, but i have no idea at which bit to use it..this is how far i've got

## "Degree mode", like my TI-89 has?...

Hi, I just bought Maple, and I'm really excited about it. I'm poking around in Maple, trying to get comfortable with it, by entering in a problem from my physics class. In this class, we use SI units, except that we express our angles in degrees. I'm trying to find an easy way to have the trigonometric functions take degree arguments. I tried "with(Units); with(Units[Natural])", and entered an expression this way: "R_x = R*sin(15*deg)", and that almost worked. There were two problems, though: 1. R is apparently a unit in its own right...not *too* much of a problem (I can choose another letter), but annoying.

## formating numbers...

How do i format numbers in maple output including comma separation and number of decimal points, etc (i.e. 33,444.00)

## Canonical Tower Function

by: Maple
I define the tower function as base^^(-1)=0, base^^0=1, and base^^1=base. In general, base^^(height+1)=base^(base^^height). My program to calculate it has four inputs: base, iter( number of iterations),h(fractional part of height), and k(integral part of height). Two outputs: answer and prec(precision). For example 1.21^^(1/3)=1.1056691794 and 1.21^^(2/3) =1.1702307336. For this program .20<base<1.44, 0<=h<=1, and iter>=20 an even integer. If base<1 or k<=-2 the answer will be complex. This cannot be used for 1.60^^(7/2)=3.0863796925. I would like to put this in my library.

## Maple 10 and 64bit Linux, part 1

by: Maple

Maple 10 comes in both a 32bit and 64bit version for Linux. It's possible to run both versions, installed to the same base location, on a machine with the appropriate operating system runtime configuration. There are some interesting performance differences between the two versions.

I'll say a few words about the installation. I installed both under /usr/local/maple10 on an Athlon64 3200+ running the x86-64 version of the Fedora Core 2 operating system. I have the 32bit...