## get coefficients with frontend and "wildcards"...

Hi there!

Suppose I have an expression

`Expr:=a*f(x[0],...) + b*f(x[1],...) + c*f(x[2],...),  `

where the ellipses represent (different) functions of x[0]..x[2]. I'd like to use frontend to get the coefficients a, b, c corresponding to x[0], x[1] and x[2]. If the function f only has one argument, that's peanuts:

## Implicit 3d plot...

Hi.  I want to plot the function U in terms of x and y,

U :=2*diff(p(x,t),x)*diff(q(y,t),y)/(p(x,t) + q(y,t) + a[0])^2;

where

## How to use saved Matlab codegeneration?...

<p>Hi </p>
<p>I have some funtio<img alt="" src="file:///C:/Users/BrianBak/AppData/Local/Temp/moz-screenshot-5.png" />ns that a generate using maple. I would like to be able to set an variable equal to the right side of these functions in matlab. I have saved the funktion in the following way. </p>
<p><img alt="" src="file:///C:/Users/BrianBak/AppData/Local/Temp/moz-screenshot-6.png" /><img alt="" src="file:///C:/Users/BrianBak/AppData/Local/Temp/moz-screenshot-7.png" /><maple>with(CodeGeneration)</maple><br />
<maple>Matlab(x^2+y^3, output = "file.txt")</maple></p>

## Why does sum do something different?...

Hi.

I defined the following functions:

## Maple's calculations are non-deterministic ?...

Hello,

I've performed the exact same calculation (using the exact same worksheet, with absolutely no changes made) last night and today and got these results:

y=[0, .4646313991, .9499094532, .5799050874, .1092604065, .4031507404, .8483735670, .6138799333, .1913933456, .3724618402, .7707837830];

y=[0, .4646313991, .9499094532, .5799050874, .1092604061, .4031507404, .8483735643, .6138799354, .1913933461, .3724618343, .7707837938];

Which are exactly the same modulo the last 3 digits.

Digits=10 in both cases.

## Dynamically build piecewise function...

Hi,

I read data into Maple, and based upon that, wish to dynamically construct a piecewise function. In advance, it is unknown how many entries the piecewise will have or where the breakpoints are.

How can I work dynamically/programmatically with piecewise functions? Is there some documentation or concept I should know about so I can help myself on this? The only possibility I've found thus far is using the sscanf function, which makes it a little more complicated than necessary.

## Plotting Implicit/Inverse functions...

Hi all, Being new to Maple, I have a rather trivial question for most out there. How does one plot x=ln(y) or any function x=g(y) to be more general? I have worked with implicitplot() as such, but it only feels like drawing a straight line for x=ln(y). Here is the syntax I used: > g := y -> ln(y) > with(plots) > implicitplot(g, x = -10 .. 10, y = -10 .. 10) Does maple expect the assignment of the full equation (i.e. g:= x = ln(y)) in order to process inverse or implicit functions? I'm obviously borking the syntax. I have searched through this forum and the help. Any information is thoroughly appreciated in advance. Phillip

## Isolate and derive a solution obtained from dsolve...

Hi (working with maple since yesterday, so question might be elementary) I have an ODE system with functions x(t,k),y(t,k), t is the independent variable, k is a parameter, as well as initial conditions. What I am aiming at is a 3-d plot of the _derivate_ d/dt x(t,k) of the first solution of the system, and t and k as horizontal axes.

## Differentiating Vector Functions?...

Hi. I recently turned over to maple 13, after using TI InterActive! for 2 years. But i am having som problems working with vector functions in maple. Here is a link to the PDF file with the exercise in TI: https://docs.google.com/fileview?id=0Bx5y79IuSOVJNTAxNmJmODAtOGY3OC00NWRhLWI0ZTgtMzBmOWJhMzYzMDMw&hl=en It's when i reach "Opgave 2d" that i get into trouble.. when i differentiate the r(t) function it just gives me an error.. "non-algebraic expressions cannot be differentiated" And im just wondering wether there are other functions in maple to differentiate vector functions?

## Defining functions within a proc/plotting within a...

Hello there.

I´m fairly new to maple, so i apologize if this is a rather "simple" question, but right now I don´t really know how to get rid of the error message that occurs.

What I try to do is define 3 components of (in this case) a function that describes a magnetic field. These functions ( seen below) depend on a few parameters (a,b,c,d,p and chi).

restart:
with(plots)

>
> PlotMfield := proc (a::float, b::float, c::float, d::float, p::float, chi::float)

## Using MAPLE to find intersection of vector functi...

Hi all,

I have a relatively simple question that you can do by hand, but I want to know, if it is possible for MAPLE to compute directly with a single command if any 2 vector functions do intersect.

eg. r(t) = <cos t, sin 2t, exp(t)> s(t) = <sin t, cos t, exp(t)> ,  -2 < t < 2

## Need to test a recursion...

I have a multivariable function, F(n, g(1,0),g(0,1),g(0,2),g(1,1),g(2,1),...,g(n,1),g(n-1,2),...,g(1,n)), of indeterminates g(i,j) (omitting g(0,0) - in other words - let L = set of all pairs of nonnegative integers, (i,j), which satsify 1<= i+j <=n) of the following form F = product over all the (i,j) in L of g(i,j)^h(i,j) / ((i!

## analyzing graphs of a function...

These are the steps that I need to do

determine the domain and range of the functioon

determine the intercepts and asymptotes of the graph

locate the x-values where f'(x) and f''(x) are zero or undefined

then i need to determine where the relative extrema and the points of inflection occur (this i should be able to do if I can get the graph)

i have to know how to do this for two kind of function for a test tomorrow I missed all week because i was sick and we are allowed to use the software on the test.

here are the functions

## Multiple crossing points???...

Hi

i am trying to code a proc that tells me when a certain function is better than another. My proc works fine for functions that have a single crossing point but it does not seem to work for inputs that have multiple crossing points.