I have been Maple  18 with no problem. Then, today, the  "=" symbol and  "+" symbol don't work.  Does anyone know what to do about this?

hai everyone. i am currently trying to solve an integration of the following ∫g(η)dη . integrate from 0 to 10.

from the following odes.

f ''' +1-(f ')² +ff ''=0,

g''-gf'+fg'=0,

with boundary conditions f(0)=0, f'(0)=λ, f'(∞)=1, g(0)=1,g(∞)=0

First, i solve the odes using the shooting method. then i used the trapezoidal rule to solve for the integration of g(eta) using the following codes

> with(student);
> trapezoid(g(eta), eta = 0 .. 10, 10);
> evalf(%);

it seems that it can not read the data from the shooting method. can anyone suggest why it is happening?

thank you verymuch for your concern :)

Hello

I wantt to assigne value to a variable that doesn't exist before the radio button. How can i do that?

Could you please help me?

I need to show that the least square solution x that I obtained as x=pseudoinverse(A).b is the solution of Transpose(A).A.x=Transpose(A).b with the smallest norm. I've obtained the norm for the RHS of this expression as well as the norm of x but I'm unsure of how to conclude that this is the lowest possible norm using these values

where A^T is the transpose of A and it's given that (A^T).A is not invertible.

I am stuck as to how to arrive at the solution for x in this case. I initially thought I could multiply both sides by the inverse of A^T reducing it to Ax=b but that was obviously wrong since A^T is itself not invertible(it is singular).

I am a middle school teacher trying to program an app where a student will type in a linear equation in any form. They are to solve this for the variable Y and graph the line. I have most of this up and running, but I would like to include a step by step help system, where after entering the equation, the students can click on a button and it will display the 1st step to solve the equation. I am using the built-in function “LinearSolveSteps” in the Students [Basics] package. Every repeated click of the button would reveal the next step. I have this working to a point, but I don't seem to be able to add the next step into the math container without deleting the contents that are already in there. I have tried rebuilding the string by using the "+" but the + shows up in the equation and it is not on a new line. Any ideas would be appreciated. Thank you.

Take a 3d plot of some uneven surface in the xyz space and you want to have the surface colored according to local z-coordinates (e.g. a valley is blue, a peak is red with all rainbow colors inbetween). For such a color-coding one can in principal select the plot option "Color->Z (Hue)". What do you do if the valley and the peak are still more or less green colored? How can you force the valley and peak to have different colors?

I have this surface which I display with the following commands:

     Belt:=plots[surfdata](Surface,color=C,labels=["x","y","z"]):

     display({...,Belt});

It all works, and the surface has nice default rainbow colors, but when I choose Color->Z (Hue) everything turns to green. Also when I manually write in the first of the above lines "color=["Blue","Red"]" the surface turns all red. The ranges of the x and y axis are larger than the z axis by a factor of about 50. Might this be the problem? How can I adjust the color ranges for my small z axis?

How would you insert a label-coordinate in this command:

textplot3d([subs(E[11]=0,x[11]),subs(E[11]=0,y[11]),subs(E[11]=0,z[11]),"Planet"]):

The following is taken from p 328 of the Maple TA manual.

\documentclass[12pt]{article}
\usepackage{ed}
\begin{document}

\begin{question}{Formula}
% This question uses randomized variables.
\qutext{Find the formula for the inverse of the function
$f(x)=\var{a}x+\var{b}$.}
\answer{(x-\var{b})/\var{a}}
\code{
$a=int(rint(9)+2);
$b=int(rint(9)+2);
}
% The above code chooses random integer coefficients a and b between
% 2 and 10.
\end{question}

\end{document}

Running it though the online compiler generates the following when Service Pack 1 checkbox is UNCHECKED

Note: Successful conversion from LaTeX to QU does not guarantee that your testbank will load into Maple T.A. correctly. Please examine the contents of the box below for any additional errors that may be generated when your testbank is loaded into Maple T.A.

l2e_pkIwct.qu: Error at line 3.
Line ended while reading variable name (missing "=" at end of name?)

(A response of "[OK]" indicates that there should be no problems uploading your converted testbank file to Maple T.A.)

and the following when it is CHECKED

...

[30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44]
[45] [46] [47] [48] [49] [50] [51] [52])
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/html-mml.4ht)
(/usr/local/latex2edu/texmf/tex/local/ed/ed.4ht [53] [54]))
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/html4.4ht)
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/unicode.4ht)
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/html4-uni.4ht)
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/mathml.4ht)
(/usr/local/latex2edu/newt4ht/texmf/tex/generic/tex4ht/html-mml.4ht)
(/usr/local/latex2edu/texmf/tex/local/ed/ed.4ht))
No file l2e_yQsgNQ.aux.
)
*
! Emergency stop.
<*> \def\production{}\input l2e_yQsgNQ.tex

Output written on l2e_yQsgNQ.dvi (54 pages, 25316 bytes).
Transcript written on l2e_yQsgNQ.log.

What's going on?

I am attempting to plot an initial value problem in Maple 18.  I have my equation defined, as well as a general solution and two particular solutions at y(0)=3/4 and y(0)=1/2.  To graph, I entered the command

DEplot(de,y(x),x=-3..3,{[0,1/2],[0,3/4]},dirgrid=[12,12],color=black,linecolor=blue,thickness=2);

but instead of returning a graph, the software gave me the error message

Error, (in DEtools/DEplot/CheckDE) extra unknowns found: sinx

The Maple support site lists this as an unknown error, and as a new user, I'm not sure what to do.  What does this mean?

hello

I have a system of equation. to solve i using DirectSearch pakage. i think in answer DirectSearch use rounding number but in answer it's second and third digit after the decimal point is important. please help me. bbw.mw

if b and c increase 0.01 and -0.01 it's ok. another main question is why by increasing the intensity answer don't change.

Dear All，

I solve an equation  as follows,

m:=dsolve({T(0) = 300, diff(T(t), t) = (min(G1, G2)-Loss)*(1/35513)}, T(t), numeric)

G1,G2, and Loss are functions of T and G1 and Loss are tangent at point A where T=600, when I　want to plot the dsolve solution by odeplot,like this

odeplot(m, [t, T(t)], 0 .. 800)]

I got a curve whose maximum value  is  600( equal to the tangent value) and actually the value should increase after passing the tangent point, Who can tell me where is the problem. Thanks.

The algorithm that I need to replicate is as follows:

real function f(x,y)

integer n; real a,b,c,x,y

f<-max(|x|,|y|)

a<-min(|x|,|y|)

for n=1 to 3 do

b<-(a/f)^2

c<-b/(4+b)

f<-f+2*c*f

a<-ca

end for

end function f

How can I define f,a as  functions that I am later using as variables(in f=f+2cf,b=(a/f)^2)? also, is n just a variable for iteration? 

Heun functions arise in the solutions of various differential equations, for instance for the Schroedinger equation for the hydrogen atom in physics, which is also of chemical interest.  Although they have been nominally included in Maple for several years, they are still in a primitive state; despite their obscurity and intractable nature, there seems not to exist much possibility, within Maple, to convert these functions into better known and characterised functions.  A similar condition holds for Lame and spheroidal functions that are invaluable in the solution of differential equations in physics but are not even mentioned in Maple. 

The compilation of mathematical functions by Abramowitz and Stegun was published half a century ago, but there are still important functions explained therein that are lacking from Maple, not to mention the successor in the NIST Digital Library of Mathematical Functions.

Integral equations are another weak component of Maple; the present content relies on a basis of work of ProfessorCorless and his student submitted to the 'Maple Share Library' -- decades ago.  Forty years ago, David Stoutemyer generated some procedures to solve non-linear integral equations in Reduce, but forty years later Maple has no benefit from that knowledge.

We can only hope that Maple 19 will remedy some of these gross deficiencies.  The teaching, learning and practice of physics will benefit from their implementation.

At the internet site of The Heun Project, a strong declaration is made that only Maple incorporates Heun functions, which arise in the solution of differential equations that are extremely important in physics, such as the solution of Schroedinger's equation for the hydrogen atom.  Indeed solutions appear in Heun functions, which are highly obscure and complicated to use because of their five or six arguments, but when one tries to convert them to another function, nothing seems to work.  For instance, if one inquires of FunctionAdvisor(display, HeunG), the resulting list contains

"The location of the "branch cuts" for HeunG are [sic, is] unknown ..." followed by several other "unknown" and an "unable". Such a solution of a differential equation is hollow.

Incidentally, Maple's treatment of integral equations is very weak -- only linear equations with simple solutions, although procedures by David Stoutemyer from 40 years ago are available to enhance this capability.

When can we expect these aspects of Maple to work properly, for applications in physics?