I would like to create a Maple Workbook of my Lattice Package so I can put it on MapleCloud. I had an email exchange with Daniel Skoog from Maplesoft about this, and he even sent me an example that looked easy enough to adapt to my purposes. Alas, it does not work. Here is the code I wrote to assemble the already extant files:

restart;
                "Maple Initialization loaded..."
# Build Lattice workbook following example from Daniel Skoog, MapleSoft:
currentdir();
 "/Applications/Math_Calc/Maple 2015/Packages/Lattice/Lattice

    Version 1.1.0 release files"
# We have all files already from the App Center submission, so just assemble the workbook
PackageTools:-Create("Lattice.maple",\
"MLA file"="Lattice.mla",\
"Lattice.help",\
"Source"="Lattice1.1.mpl",\
"Build procedure"="Lattice1.1.mw",\
"Manual"="The Lattice Package Users Guide.mw",\
"Release Notes"="V1.1 Release Notes.rtf");
Error, (in march) unable to attach worksheet file The Lattice Package Users Guide.mw

When I look at the created workbook (Lattice.maple), the only members included are Lattice.help, the Build procedure Lattice1.1.mw and the source file Lattice.mpl. In particular, Lattice.mla is not there, which is the most important one.

What am I doing wrong? What does "march" (which sounds like machine architecture) have to do with it??

I also don't quite know how to "install" it. I assume I just put the whole workbook into a directory accessible through libname ?

Mac Dude

PS: I could have sorted this privately with Daniel, but this may be of interest to others as well so I hope he'll answer through this forum.

Lattice1.1_workbook_maker.mw

Maple help pages are terrible.  Sorry, but this is true.

I am looking for one example of how one is supposed to open a file and correctly check that the open was successful and no error occured, all done in code. As in a script.

All what help in fopen says is that if this and that, it generates an error.

            "otherwise, fopen generates an error. "

OK. But to check for this in code? Why not show an example? the help page on iostatus just lists possible errors. Again, not a SINGLE example of actual Maple code showing how to actually check or handle an error. It just says to call iostatus() and shows the output without an example of what to do next and what to check for.

Lets say one does this:

fileName := "C:\\foo.txt";
fd       := fopen(fileName,WRITE):

Now what? How to check the above was successful? Do I need a trap and catch? catch what? Do I need to check for fd being greater or equal to zero and also use trap in addition? And if an error happens, how to know what it is? How to to format the message, etc.. all in CODE (not interactive) and not by saying just look at the screen and see if there is an error message.

Spend 30 minutes in the help pages and could not find ONE example that shows how to actually check for errors.

I have no idea who writes Maple helps pages, but I find the help pages useless most of the time.

Compare the help for linux fopen for example, where is gives exact details of how to handle the error and find the exact error, all in code.

Sometimes dsolve returns solution as implicit, even when not using the `implicit` option. For example

restart;
ode:=diff(y(x),x)=(x*y(x))^(1/2):
sol:=dsolve(ode,y(x));

Gives

Which is the same result if I had used 'implicit'.

Is there a way to tell dsolve not to do this? is it becuase it can't solve for y(x) from the above?

Maple 2017.1

when i want to get awenser i have to solve it for 36 equation and 36 variabales
but maple will not give me a solution (just toss me back my variabales ) i dont know whats wrong
it will give me an awenser for lower like 20equ and 20var ?
parameters :

there is m for power an equation (equation^m) its between 2 , 2.5 , 3 , 4
and N give 2N+2var and 2N+2equ
its a hard calculation i copy it here hope u get it

h= "a number "

p := proc (x) c[-N-1]*x^2+1 end proc

dp := diff(p(x), x)

ddp := diff(p(x), x, x)

DELTA2 := piecewise(k <> j, -2*(-1)^(j-k)/(j-k)^2, k = j, -(1/3)*Pi^2)/h^2

DELTA1 := piecewise(k <> j, (-1)^(j-k)/(j-k), k = j, 0)/h

DELTA0 := piecewise(k <> j, 0, k = j, 1)

PHI := proc (x) ln(sinh(x)) end proc

dPHI := diff(PHI(x), x)

ddPHI := diff(PHI(x), x, x)
 

for i from -N-1 to N do x[i] := ln(exp(i*h)+(exp(2*i*h)+1)^(1/2)) end do

variabales : c[-N-1],c[-N],c[-N+1]...c[N-1],c[N] total 2N+2 var

My equations

POL := seq(simplify(eval(sum(c[k]*((eval(2*dPHI*DELTA1), x = x[j])+eval(x[j]*ddPHI*DELTA1, x = x[j])+x[j]*(eval(dPHI^2, x = x[j]))*DELTA2), k = -N .. N)+eval(ddp, x = x[j])+2*(sum(c[k]*(eval(x[j]*dPHI*DELTA1, x = x[j])+DELTA0), k = -N .. N)+eval(dp, x = x[j]))/x[j]+(c[j]*x[j]+p(x[j]))^m, x = x[j])), j = -N-1 .. N)

solving

K := fsolve({seq(POL[v] = 0, v = 1 .. 2*N+2)})

it can calculate for m=2.5 , N=15 , h=0.29669

if you can calculate it for m=3 , N=17 , h=0.41600

Everytime I start Maple 2017 I get a window asking me to accept incoming connection even though I did not put any restriction in System Preferences-Security-Firewall.

Is it normal?

Thank you

hello...how i can remove this error?

thanks

33.mw
 

Download 33.mw

in my solution is 0.0000 . how can show it 0 and how can i show the solutions for example 10^-30 to zero(round to zero)

1.mw

I want to plot a function f(x,y)=x^3-2x^2y. But I only want to plot values where $x^2+y^2 <= 1$. So far I specified the plotting range in the standard way, but I really need to specify it like I described. I want to use plot3d.

hello...how I can pdsolve three equations with related boundary conditions?

please help me.

thanks...

Download for_site.mw

hello...how I can pdsolve three equation with related boundary conditions?

please help me.

thanks...

for_site.mw

Maple 2017.1 on windows 7.

This is VERY frustrating. If I have a string which is too long (do not blame me, it is Maple's output), and  try to save it to text file using fprintf(), then Maple decides to insert CARRIAGE RETURN at about each 1,000,000 characters intervals. 

So if the string happened to be 5 million chars, and instead of getting one long line in the file for this one result, It writes 5 lines in the file.

Becuase of this, I can't postprocess this output, since the program that reads the file expects one line per one result. So it fails to parse it. And having to post process the file to correct this is not easy at all.

Why is there a limitation of writing long string to a file without it being chopped of like this? Is there a way to work around this? Here is a MWE

restart;
directory("C:\\bug");
result:=int((a+b*tan(e*x+d)+c*tan(e*x+d)^2)^(1/2)*tan(e*x+d)^2,x):
result_as_string:=convert(result,string):
fd := fopen("out.txt",WRITE):
fprintf(fd,"%s\n",result_as_string);
fclose(fd);

As you can see, I wrote the result as one string. Now if you look at the file out.txt in the directory (you might want to use good editor for this, such as vi or textedit), you will see many lines in there, and not one long line as expected. Or you can run this code

restart;
directory("C:\\bug");
number_of_lines :=0:
line:=readline("out.txt"):
while line <>0 do
   number_of_lines :=number_of_lines + 1:
   line:=readline("out.txt"):
od:
print(` number of lines read is `,number_of_lines);

The above gives

                ` number of lines read is `, 24

This problem now means I am not able to continue with what I am doing. Does this happen on other platforms?

I think this happens due to Maple limits

      `[Length of output exceeds limit of 1000000]`

However, I am NOT dispalying anything on the screen. This is all going to text files.  It seems Maple output limits of 1,000,000 is confusing fprintf() to a file as well?

Perhaps I am being stupid, but I have a problem with functional operators, more specifically with looping through a collection of them. Consider the following code (just a study case):

nonIdMaps := []:
for f in [x -> x,x -> 2*x,x -> 3*x] do
   f,f(y);
   if f(y) <> y then nonIdMaps := [nonIdMaps[],f] end if
end do;
nonIdMaps,map(f -> f(y),nonIdMaps);

There are two things I do not understand about this output: 1.) Why the f's rather than the specific maps as given in the list? 2.) Why two times 3*y in the last line, rather than [2*y,3*y]? (this issue being of course quite likely a consequence of the first one). This behaviour can be compared with the following:

nonIdMaps := select(f -> f(y) <> y,[x -> x,x -> 2*x,x -> 3*x]):
nonIdMaps,map(f -> f(y),nonIdMaps);

the output of which I do understand, being as I expected it to be. I guess that there are some scoping rules I do not understand, or what?

Dear friends,

I have to solve the BVP of the following type:

(x-1)*y''(x)+y'(x)=1+x, y(0)=1, y(1)=1

Expressing the highest derivative (y''(x)), we get a singularity at x=1.

So, as recommended, the method bvp[middefer] (or bvp[midrich]) is used:

dsolve({(x-1)*diff(y(x), x$2)+diff(y(x),x) = 1+x, y(0)=0, y(1)=1}, type = numeric, method = bvp[middefer], y(x), 'output' = Array([seq(k/10, k=0..10)]), 'abserr'=1.0e-3, 'maxmesh'=100)

Maple generates the following error:

Error, (in dsolve/numeric/bvp) unable to achieve requested accuracy of 0.10e-2 with maximum 100 point mesh (was able to get 0.82e3), consider increasing `maxmesh` or using larger `abserr`
But as I increase maxmesh, the achievable accuracy (reported in "(was able to get XXX)") decreases:

for

maxmesh = 200: 0.19e4

maxmesh = 500: 0.54e4

maxmesh = 1000: 0.12e5

maxmesh = 5000: 0.73e5

and so on.....

How to solve this equation with desirable accurancy and usage of Array as output?

Using Tools -> Check for Updates, I have just tried to update my Maple installation from 2017.0 to 2017.1. The download itself went without a hitch, but then nothing happened. In view of the fact that I clicked a button titled 'Download and Install', I would certainly expect the installation to have started automatically after download. Are anyone else experiencing the same odd behaviour?

PS: Related question of mine is Automatic update of help pages?

Hi, friends

I need to calculate the double integral over a non-rectangular domain.

Say, the domain is the triangle (in red)

When I enter

int(int((x^2+y^2)*`if`((y-x-1/2 <= 0) and (y+2*x-2<=0) and (y+x/2-1/2>=0), 1, 0), x=0..1, numeric = true), y=0..1, numeric = true);

or 

int(int((x^2+y^2)*eval(`if`((y-x-1/2 <= 0) and (y+2*x-2<=0) and (y+x/2-1/2>=0), 1, 0)), x=0..1, numeric = true), y=0..1, numeric = true);

an error occur (Error, (in int) cannot determine if this expression is true or false: y-x <= 1/2 and y+2*x <= 2 and 0 <= y+(1/2)*x-1/2)

For me, it is desirable to write boundary conditions in the int operator itself, not as a separate expession.

Consider the following:

with(Physics):
Setup(anticommutativeprefix = psi):
psi^2,psi__1^2,psi__a^2;   # double underscores

Why does the square of psi__a (double underscore) not vanish as well? Or, perhaps, more to the point: why is psi__a not as well considered Grassmann-odd by Maple? Is this counter-intuitive behaviour intentional, or is it a bug?