Ok so I managed to get my data into a google spreadsheet by using a google app script (JavaScript in the cloud).
The data is updated daily. I now want to access it from Maple. Axel has helped me write the following
procedure to do just that for (https websites and not just http):

X := proc (Url) local theDLL, URLDownloadToFile, myDirectory, myFile, Destination, DL;

theDLL := "C:\\WINDOWS\\SYSTEM32\\urlmon.dll";

URLDownloadToFile := define_external('URLDownloadToFileA', pCaller::(integer[4]), szURL::string, szFileName::string, dwReserved::(integer[4]), lpfnCB::(integer[4]), 'RETURN'::(integer[4]), LIB = theDLL);

FileTools:-MakeDirectory("C:\\mydir");
myDirectory := "C:\\mydir";
myFile := "data1.csv";
Destination := cat(myDirectory, "\\", myFile);

DL := proc () URLDownloadToFile(0, Url, Destination, 0, 0);
ImportMatrix("C:\\mydir\\data1.csv", source = csv)
end proc;

return DL(), FileTools:-RemoveDirectory("C:\\mydir", recurse = true, forceremove = true)

end proc:

X("https://docs.google.com/spreadsheets/d/1L5-yUB0EWeBdJNMdELKBRmBQ1JJ0QymrtDLkVhHCVn8/edit?usp=sharing");

However now I get an error message saying:

Error, (in ImportMatrix) no delimiter found after line 768, column 2

Any ideas how to solve this?

Hoe do you plot two vectors of data as a bar plot or historygram. I tried the statistics package but could not plot a bar plot that shows the proper relation of numbers in vector x to numbers in relation to vector y. Vector x contained years as data, and vector y contained for example crime data per year.

Hi,

I am working on making a population balance model for gas bubbles is a stirred reactor. I have data in excel about the bubble size and need to make a population model to compare the experiment with theoretical findings.

But I have not much experience in population balance modeling. Is there anyone who has an example of a solved population balance model in maple? This would help me greatly in understanding the subject. I would want to use the Luo and Svendsen model as I found it most matching with the result.

Kind regards, Hasselhof

I'm displaying two plots - one a line and one a series of points. The idea is that I'm showing a fit curve onto a set of experimental data. I want the dots, which are fairly fat, to sit on top of the line. But whichever order I display the two plots in, the line is sitting on top of the dots. This looks wrong. Does anyone know how to put it right?

hi, I want calculate lambda(lagrange multiplier) for lane emden type equation, I have made a programme for it but here is error at the end of programme,plz help

lambda.3rd.mw

hello people

I have this computation which has to do with my undergraduate project and each time I compute some work (vary parameters), it seems to evaluate forever. although my computer isn't recent and has 2GB of RAM the computation didn't seem to me as much of a task for it. computation works fine with some parameters as 0 but the moment I change it to a natural number, it evaluates forever.

Is there anyway I could speed up computation in maple? or do I just need a faster computer? but I have a dead line for next week. can I upload my worksheet for someone here to help me execute? 

thank you in advance. 

Hello everybody,

my question concerns the visualizing possibilities of maple:

can maple visualize complex functions? (f(z): C->C)

If so, which possibilities do i have und what is the command for it? Maybe as a coulour diagram, as a vector field (f(x): R^2->R^2) , or as mapping of sets (e.g. curves, grids into new curves and curved lines)?

Thanks in advance

regards

Nikita

PS: I am using maple 18.

I am trying to see how do I have initial conditions in a system of differential equations. This is an example problem, which doesn't work. What is wrong? Thank you.

I want to make a package that I have created work with the LinearAlgebra package that comes with Maple. My package loads into a worksheet fine, but when I try to use one of my procedures, most of which depend upon procedures in the Linear Algebra package, the executable part of my procedure from my package is simply echoed to the screen and not executed. If I then copy the echoed part to a command prompt then it executes fine. How do I make my package use the commands in the Linear Algebra package?

Hello!
Try to consider the following system of differential equations:

sys := diff(U(ksi), ksi) = (y(ksi)-(1.5*(1+0.01*ksi))*U(ksi)/ksi)/(1.5+0.015*ksi+0.002*ksi^2),
diff(y(ksi), ksi) = U(ksi)*(0.002+(1.5*(1+0.01*ksi))*(0.002*ksi^2)/(ksi^2*(1.5+0.015*ksi+0.002*ksi^2))-19.3^2)-y(ksi)*(0.002*ksi^2)/(ksi*(1.5+0.015*ksi+0.002*ksi^2))

with the boundary conditions: cond:= y(0.8) = 0, y(1) = 0

And Maple gives me zero solution for this system , i mean U(from 0.8  to 1) = 0 and y(from 0.8 to 1) = 0

How can i get some other solutions?


P.S. i need numerical solution => dsolve( [sys,cond],type= numeric)

Please, i need some help.

I want to calculate this limit

limit((b^(d+1)-1)/((b-1)*b^d), d = infinity)

but it always return limit((b^(d+1)-1)/((b-1)*b^d), d = infinity)

Is it becaus it cant recognize what b symbol is ?

Hi,

I am trying to use implicit plot. The plot is OK but I want to put labels such as what Latex produces :

$\frac{\Omega}{\omega_n}$ for x axis and $a_0 \mathrm{(m)}$ for y axis

How can I apply this in my maple code as below:

plot1:=implicitplot(a3, Omega_r=1.5..2.5, a=0.00000001..0.1, labeldirections=[horizontal, horizontal], axes=boxed, labels=["W/w_n",typeset("a_0 (m)")], labelfont=[SYMBOL]):

What I have put as bold does not work for me, it is making everything in Greek :) . I want combination of Greek and math.

Thasnks,

Bahareh

Hi!

This question is related to http://www.mapleprimes.com/questions/204419-Derivatives-Of-Splines-Are-Not-Defined and http://www.mapleprimes.com/questions/42114-Problem-With-Spline-Integrating , however I have not been able to apply the solutions given there to my problem.

I have a set of points given by

and certain function value points given by

where e1 is the function I am approximating.

Using

I come up with my piecewise function.

When I do diff(e4,x), however, the points at the nodes show "float(undefined) x=0.2..."(the node).

As it turns out, the value of the derivative on the left of the node is not equal to that of the right side by a factor of 10^(-7), in other words, numerically unimportant but high enough for maple to realise it is not the same number. How could I tell Maple that I am happy choosing, for example, the value given by the function on right side of the node?

I welcome any suggestions.

Many thanks in advance.

Every time I try to write a procedure I get stuck.

This time is no different:

restart;

global a:=0.081819221, PI:=3.1415926535897932384626433832795;
Ecce:=proc(lt)
lat:=lt*(PI/180);
b:=((1-a*sin(lat))/(1+a*sin(lat)))^(a/2));
t:=ln((tan(PI/4)+lat/2));
d:=3437.7468*t*b;
return d;
end proc;

I digit the following to get a result
Ecce(45.2112);

and this is what I get (in blue)
Ecce(45.2112)

Every single time. I can never have a procedure that works right away. It's getting on my nerves