Hi guys. I'm trying to do something like this: add(add(f[m-k,k], k=0..m), m=1..d); and I want to get Maple to print the coefficients i.e. f[1,0]+f[0,1]+f[2,0]+f[1,1]+f[0,2] etc. I guess what I'm stuck on is how the Array for f should be defined? Any ideas? Thanks, Tom

I need help solving the following integral with Maple

int(erfc((R+3*t)/(6*t^1/2)),t=0..1)

I have a new one :) I need to find the critical points and tell their nature of a 3 variable function. It's a new thing for me and i'm not sure if i did it ok, here's what i have tried:

g := 1-2*x+3*x^2-x*y+x*z-z^2+4*z+y^2+2*y*z;

ex := extrema(g, {}, {x, y, z}, 't'); - stores the extreme value of f in ex

evalf(ex); - displays the extreme value in decimal

t; - contains the critical points of f

evalf(t); - displays the critical points in decimal

Here's what i have to do. i have a system formed of 3 equations, and i have to find the solutions ( there may be only one ), and the make sinus out of it evaluating it with 5 digits.

I am finding problems with plot first:

I am trying to find out all the real solutions of a system of 2 eqns and i just can't figure it out. Here's what i'm trying:

>eqn1:=x+y=9;

eqn2:=x+y-sin(x*y)=7;

solve({eqn1,eqn2})

 

After i hit enter, i get this warning:

 

Warning, solutions may have been lost

 

I'm completely lost !:(

 

Dear all:

   I assume this is an easy question, but I simply couldn't find an answer: How to sample from a multivariate normal distribution give a mean M and covariance matrix Ccov? The statistics package seems to only contain 1-d distributions.

Thanks a lot,

Peter

plot (arccos(cos(x)),x);

At x=0, arccos(cos(x)) should be shown on the graph at (0,0),  As I zoom in I find that Maple draws it at closer to the point (.01,-.01) not at all at (0,0)

How do I create 3D polygone by a list of points using maple.?

I convert following differential equation to the s domain: restart: with(inttrans): > DV:=diff(y(t),t$2)+3*diff(y(t),t)+2*y(t)=diff(x(t),t): > x:=t->10*exp(-3*t): > laplace(DV,t,s); As solution I get: s^2*laplace(y(t),t,s)-D(y)(0)-s*y(0)+3*s*laplace(y(t),t,s)-3*y(0)+2*laplace(y(t),t,s) = -30/(s+3) It's not really a Maple problem but I don't understand why the right hand side of the equation is -30/(s+3) . When I transform the right hand side of the differential equation manual to the laplace domain I would do it as: diff(x(t),t) = s*X(s) = s * 10 /(s+3)

Is there a way to solve following equation in maple? I have already tryied intsolve and dsolve without succes. DV:=diff(y(t),t)+5*int(cos(t-tau)*y(tau),tau=0..t)=10; Thank you, Pieter

An annoying feature of Maple is that if it crashes (all too often) & you have not given your worksheet a name, the file is lost despite having activated Auto-Save.

1)   Is the previous statement correct for Maple 9.5?

2)   If so, has this bug been corrected in later versions?

Alla

I create a continous random variable having an arbitrary pdf and characterize the corresponding distribution:

pdf := piecewise(a <= x and x <= b, 1, 0): f := unapply(pdf, x): R := Statistics:-RandomVariable(Statistics:-Distribution(PDF = f)): `assuming`([map(apply, [Statistics:-MGF, Statistics:-CGF, Statistics:-PDF, Statistics:-CDF, Statistics:-Moment], R, t)], [a < b]) ;

Hello,

I have a big problem with the plot command :

I have tried to do a densityplot with cylindrical coords, but it doesn't work, it seems that maple can't do it. Do you have any suggestion to do this ?

So I decided to switch to plot3d - contourplot even if i would rather like densityplot. The problem is that i can't show the whole plot : maple only shows me a quarter of what i want :

contourplot( f (r,alpha), r=0..5, alpha = 0..2*Pi, coords=cylindrical );

where is the rest of the function ?

gerald

thanks for your help !

Hello,

I'd like to create a multiple variables function with a procedure, the problem is that the number of vars depends on the parameter n :

f:=(x1, x2, ..., xn) -> ...

how to define this function ?

 

I ve tried to do this, but i doesn't work :

var:=seq(d[i],i=1..n)
f:=(var)-> ...

even with a array instead of the seq, it doesn't work ... i'm desperate

 

thanks !

I've been trying to solve Project Euler's first problem: If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. I've come up with: natural:=proc(n); local i,s; s:=0; for i from 1 to n do if irem(i,3)=0 or irem(i,5)=0 then s:=s+i fi od; return s; end; but I also get the error message: "Error, unexpected `local` declaration in procedure body" Could you please tell me where I've gone wrong? Thanks in advance