We can pull values of a list

a:=[2,5,g,f,5,h];
 

a[3];
                g

a[2];
                5

etc... but it doesn't work in reverse.  You can't place a value in a certain position in a list

Hello,

does the verify command not work for trig functions ??

verify(sin(x)/cos(x),tan(x),'equal')

gives 'FAIL' rather than 'true'

 

Is there a function for checking whether or not the LHS and RHS of my trig identity match ??

 

 

I'm running a relatively complicated maple file on my mac computer and it's give me the following error message: Kernel connection has been lost. The Kernel returned the following error message: Execution stopped: Memory allocation failed. Please see? alloc for more details. you should sace this worksheet and restart Maple kernel. Firewalls have been known to cause problems with kernel connections in Maple. Please ensure that any firewall software is configured to allow Maple to creat connections to the kernel.

I'm posting it here to keep a record for myself.

my second blog post, aka "the lost blog post", is here.

Still some way to go. The following still needs to be tweaked case by case. And it can be made more compact too. Are the arrows flying so much faster in the top triangular area or are the arrows not printing where I expected them to ...

I am trying to create a 3d plot of a simple function which evenly distributes a force around the end of a pipe as a function of it's angle.  The equation is

fy :=FORCE/(2*Pi*R)*COS(PHI), PHI=0..2*Pi, R = CONSTANT

I would like to create a wire-frame, shaded, cylindrical plot showing the variation in force as a function of the angle phi.

Thank you in advance for your assistance.

funny that, how do I go from first blog post to third blog post!?!?!

that's because my second blog post appears as a comment to my first blog post.

you've just got to learn...

Since much of what I post couldn't possibly be of interest to anyone else, I thought I'd use the blog. If I remember its existence, I'll try to post here stuff to myself. After all it's less likely to be lost here than in the maze of my harddrive.

Hi everyone. Is there any way to keep auto-rotation of three-dimensional graphics? If so, how to do it for complex graphics created by the function plots[display](G1,G2,..,Gn)?

I want to find a tagent lines to the below contourlines for a function  U := Q[a]^alpha*Q[b]^(1-alpha); given any

value of Q[a] and Q[b]. I know the slope of such a tagent lines but I dont know the intercept. How can I derive such an equation ?

I would like to customize arrows of motion in a phase diagram. The system is the following, with critical point (1,1):

xdot := diff(x(t),t) = x(t)-y(t):
ydot := diff(y(t),t) = y(t)*(1-x(t)):

with phase diagram (the black line is the stable manifold of the system):

What keyboard configuration must have the Win XP to use the keyboard shortcut "Shortcut Keys" and not the key combination "International" to introduce 2-D math expressions. I refer to the help "2-D Math Shortcut Keys and Hints".
The configuration I have enabled is:
Input Device Language: Spanish.
Keyboard layout / IME: United States International.
Gracias
HerClau

 

when the expression is short, the 'collect' can works,but the expression is longer,it is different.for example: gg1 := collect(expression, z)

Hello:)

Im trying now to make a program that does the same thing as BackwardSubstitutes in maple
I tried 2 things


I tried combining the matrix and the vector in the procedure but its not working

substitutioninverse := proc (matrice, vecteur)
local n, m, j, i, resultat, V, matrice2, a;
matrice2 := [matrice, vecteur];
m, n := Dimension(matrice2);
 V := Vector(m);
for i to m do
 resultat := 0;
for j from n to 1 do

Hello, In Mathematica, one can plot a region where an inequality is true by using the RegionPlot[] function. E.g. if the region (x^2 + y^2