## Equality of sets (and sets of sets) of lists of fl...

I am generatings sets and lists of points [x,y,z] where x,y,z are floating point (real) numbers. And sets and lists of such set, etc. The computations which produce the lists and sets need to be done with Digits set to some large value but I want to consider two such sets or lists or sets of such sets, etc, to be equal if the components x,y,z, of the points in the sets etc, are equal to say 8 decimal places. Can anyone suggest a good, hopefully simple, way to do this? Applying evalf[8] to all expressions doesn't work. I have a very messy way to do it, but there ought to be a better way.

## RPN in Maple 9.5...

Is there any way of inputting data into maple using RPN as I have used RPN for years on my calculator and now have to use maple for my college course and I find inputting information takes too much time (using brackets etc.) I am using maple 9.5.

## Select a sqrt from an expression...

Given an expression such as: k:=sqrt(x)+sin(x)+exp(x)+3+sin(y); what is the most effective way of extracting the part of k that contains any/all square roots? I've played around with selectfun and select, but just can't seem to get anything out of them...I can seem to pick out any trig and exp type functions, but not the sqrt?

## Integration incorrect with assume command, correct...

In trying to answer a question for one of my students I found the following strange behavior: The probability density for the time t that standard Brownian motion started from 0 first hits the value a > 0 is: f := a*exp(-a^2/(2*t))/(sqrt(2*Pi)*t^(3/2)) Then the expected value of this hitting time is: int(t*f, t = 0 .. infinity) Maple 11 gives the answer signum(a)*infinity which is correct, as long as one understands that signum(a)=1. However, if one now assumes that a > 0 and integrates, then the answer is incorrect:

## Can you help me with Bessel functions?...

a:=evalf(sum((-1)^n*BesselK(-2*n+1,1)*BesselJ(2*n,-1),n=-infinity..infinity)); a1:=evalf(sum((-1)^n*BesselK(-2*n+1,1)*BesselJ(2*n,-1),n=-100..100)); a := 0.02456830552 a1 := 0.5233322456 Can you undestood me Why a<>a1? And how it calculated in Maple 10? Thank you before!

## Printing Problems with Maple 11.02 under Mac OS...

Maple
Maple 11 has been working flawlessly for me under Mac OS X Leopard, with both updated. However, while the screen output appears to be fine, the Times New Roman (and other?) fonts seem to disappear and are replaced by a sans serif font (like Helvetica or Geneva). This occurs whether I send the output to a postscript laser printer (HP 2200) or to a non-postscript inkjet (HP 5550). I vaguely remember having a similar problem years ago, i.e., prior to Mac OS X. Has anyone else encountered this problem? Has anyone who encountered this identified a solution? So far, I'm stuck exporting my resu

## trigonometric function to sinc function...

Hi - Does anybody know of a command that can convert all trigonometric functions in an expression into sinc functions (not hyperbolic). Something like convert,sincos but for sinc function. Thanks.

## Dragging curves in maplets?...

Hi, I was wondering if it is possible to drag a curve from one plotter to another in a maplet? Is there a way to do this with Java/OpenMaple? Regards, Art

## multiple plots...

Hi i am currently using maple 10 student edition and is trying to reduce the number of graphs i need to display. here are the following plots i have 1) implicitplot(x^3+3*x*y+y^3 = 1, x = -2.5 .. 2.5, y = -2.5 .. 2.5) 2)display([polygon([[-1, -1], [1.50322, -.503215], [-.503215, 1.50322]])], scaling = constrained) 3) (plots[display])((plottools[line])([-1, -1], [.5, .5]), color = red) is it possible to combine all 3 plots into one? or even 2. another question is in plot number 2 I drew a triangle. is it possible to make it show the angles of the triangle as well as the length of the sides on the plot?

## Expanding trig functions...

Can anybody help me how to convert (in both directions) the sums of trig functions like sin A + sin B = 2 sin ½(A + B) cos ½(A - B) Simple expand and combine commadns do not work in this case.

## Solving equations...

Hey guys, I want to solve an equation using maple.. for example, say I have the values for radius, length, and resistance.. and i want to find the value for conductivity, how would i do this? Assuming the values for radius, length, and resistance are 1, what program would I write to get maple to solve for conductivity. the equation is p=(L/RA) where p is conductivity, L is length, R is resistance, and A is radius... i know these are not the real names for the variables, but this is an example. I was thinking eq:= p=L/RA; L=1;R=1;A=1; Solve(eq,p); However this is not working. Any help for a maple newbie?

## Using The "commutator" Command In The "tensors" Pa...

Can the commutator command in the tensors package be used with tensors of rank greater than 1 ? I recently tried to prove the jacobi identity using the 2 x 2 Pauli Matrices, that I created as arrays, but kept getting an error message saying something about the improper rank, of the arguments of the commutator command. I noticed in the help pages that the arguments of commutator must be of rank 1. I also tried all combinations of covariance and contravariance of the pauli matrices, but nothing worked. Can anyone help with this ? Is there any way to get around this ? thanks, v/r,

## How do I use Maple for taking notes(symbol entry w...

Hi, I've been pondering using Maple 11 to take notes in a class. My backup plan is to use Lyx or a Latex front end. When I click on a symbol in the menu the symbol is inserted typeset as if it had been handwritten. When I enter certain symbols such as "forall" and "exists" they show up as text rather than the symbol. I've tried the "convert to 2D math" option but that has no effect. Is there a way to enter symbols and have them typeset by typing them out(like \forall ) or must I click on the buttons for it to work? Thanks.

## Parsing a value to Int, arrays in procedures...

First a thank you is in order for gkokovidis for helping me with a problem earlier. The brief story is I am trying to animate a certain box on a 30 degree slope. In order to put it together, I need to be able to turn it into a an array. In order to set an array, I need to be able to parse a certain value to an integer. Let me show you the code thus far. ``` restart: with(plottools): with(plots): c := rectangle([0,1], [1,0]): d := rectangle([1,2], [2,1]): e := rectangle([2,3], [3,2]): f := rectangle([3,4], [4,3]): g := rectangle([4,5], [5,4]): IPLaunch:=proc(v0,m) local g,a,t,S,h,T: ```