a := 18; b := 2; c := 1; d := 1; f := 1; DEtools[phaseportrait]({diff(x(t), t) = a*x-b*exp(x)*y/(1+exp(x))-f*x*x, diff(y(t), t) = -c*y+b*exp(x)*d*y/(1+exp(x))}, [x(t), y(t)], t = 0 .. 100, {[x(0) = .1, y(0) = 18], [x(0) = .1, y(0) = 27], [x(0) = .2, y(0) = 28], [x(0) = .5, y(0) = 16], [x(0) = .6, y(0) = 14], [x(0) = .7, y(0) = 8], [x(0) = .7, y(0) = 29], [x(0) = 1.0, y(0) = 18], [x(0) = 1.0, y(0) = 22], [x(0) = 1.2, y(0) = 20], [x(0) = 1.5, y(0) = 20], [x(0) = 1.5, y(0) = 24.0], [x(0) = 1.6, y(0) = 26.0], [x(0) = 1.7, y(0) = 28], [x(0) = 1.8, y(0) = 21], [x(0) = 2.0, y(0) = 9], [x(0) = 2.0, y(0) = 28]}, x = 0 .. 2, y = 0 .. 30, dirgrid = [13, 13], stepsize = 0.5e-1, arrows = SLIM, axes = BOXED, thickness = 2)

Is there an elegant way to plot in 3d only the portion of the function f(x,y)=sqrt(25-x^2-y^2) for which 9 <= x^2+y^2 <= 16 ? I'm looking for a nice plot that shows it against the whole sphere with radius 5, so that it's clear which part of the sphere is cut out.

Hi,

It might be very silly question, but i dont know why it is not working out. So here is the question. In the attached maple shhet when i am trying to substitute eta(t)=epsilon*z(t) then it is not making that susbtitution for differential operator. Apart from that when i m collecting epsilon terms then also it not collecting it.quesiton.mw

Regards

Sunit

Dear Community,

I get this message

'EQU' is implicitly declared local to procedure 'Z_DAK_FSOLVE'Problem with procedurefor a procedure, and  cannot go further. How can I avoid it?

Tx for the help in advance,

best regards

Andras

Z_DAK_PROC.mw

Below I try to use units for a simple expression, where "m" and "mm" is added on Windows using Ctrl-Shift-U.

Why does the value with unit "1 [[m]]" not show as "1 m" in (1), but simply as "m" ?

Why does the addition not result in "2 m" ?

At least I had expected the addition to be made when using "evalf()".

I have Maple 2016 on Ubuntu 16.04.  I get an error message when attempting to plot with an x11 device, that means I have missing fonts.

I do not get this error message on Ubuntu14.04, so, I think the difference is in fonts installed.

plotsetup(x11)

> plot([sin(x),cos(x)],x=-Pi..Pi);
> Maple X driver failure:BadName (named color or font does not exist)Warning: Cannot convert string "-adobe-helvetica-bold-r-normal--14-*" to type FontStruct
Warning: Cannot convert string "-adobe-helvetica-medium-r-normal--14-*" to type FontStruct

I have xfonts-100dpi and xfonts-75dpi installed.

Any idea what fonts I need to fix this?

Tom Dean

Hi Maple People,

I have this Maple command -

printf("%g",p)

where p is a variable I assign.  My problem is that I want to put a new line in the display.

What is the appropriate command?

Regards,

Matt

Hi all,

I have three points in 3d space say A1=[a11, a12, a13]; A2=[a21, a22, a23] and A3=[a31, a32, a33]. I want to fill the triangle formed by these points. How can I do that?

Thanks is advance.

Hi all,

I have a 3D graph and when I right click on the surface, under style, I can see the option of contour. When I click on that I can see some contour associated with the surface. I want maple to show the values for each contour when I observe it from the top . I want to copy and paste some surfaces in a same figure and campare the contours.

Thank you

rather than last time saved file result?

When I open maple script file, it display the result which file created.

however, not the latest result 

it need to move cursor to the end of script and press enter again.

I wish to delete the rows that have imaginery components from my results Matrix. Have tried many variants of for loops etc.

Download matrix_imaginery_elements.mw

I have the following command.

with(StringTools);
message := `Kajian ini mempunyai tiga objektif pertama seperti yang ditunjukkan dalam bahagian 1.11. Objektif tersebut harus`;

m := convert(message, bytes);

block := map(convert, m, binary);
block := map2(nprintf, "%08d", block);
block := map(proc (t) options operator, arrow; [seq(parse(convert(t, string)[i]), i = 1 .. length(convert(t, string)))] end proc, block);

block := [[0, 1, 0, 0, 1, 0, 1, 1], [0, 1, 1, 0, 0, 0, 0, 1], [0, 1, 1, 0, 1, 0, 1, 0], [0, 1, 1, 0, 1, 0, 0, 1], ........]

with(Bits);
for i to l do
for j from 3 to 7 do
block[i][j] := 1-block[i][j];  //used to flip bit in between 3rd to 7th bit in a block
end do;
c_block[i] := block[i];
end do;
c_block1 := [seq(c_block[i], i = 1 .. l)];

Error, assigning to a long list, please use Arrays

May i know how to solve this problem? I need to change some bit in a list but receive error when there is more than 100 elements in a list. Thank you.

I have a Document that I have been putting together.  When I insert a Subsection into a section below the title I get a 1D-math input command symbol.  Is there a way to prevent this from happening?  I have not had this problem before. 

It appears there is something confused in the startup of the document because when I start a new document and this doesn't happen.

It's almost like when I insert the subsection it converts that part to a worksheet?????

i'm using maple in a research but i want to add a recursive function h_m(t) in 2 case : if m is integer positive and not, 
la formule est donnée comme suit : 
  if (mod(m,1) = 0  and m>0) then  h:=proc(m,t)  local  t ;  h[0,t]:=t ;   for  i from -4 to  m  by  2 do  h [m,t]:= h[0, t]-(GAMMA(i/(2)))/(2*GAMMA((i+1)/(2)))*cos(Pi*t)*sin(Pi*t)  od:  fi:  end;
and i wanna to know how to programmate a Gaus Hypegeometric function. Thank You

Dear all,

I am trying to solve the following system of equations by using dsolve, but I get the error:  error, (in RootOf) expression independent of, _Z, could you please help me to solve it. Thank you.

restart;
Digits := 20;
with(plots);
Nr := .1; Nb := .3; Nt := .1; Rb := 0; Lb := 1; Le := 10; Pe := 1; ss := .2; aa := .1; bb := .2; cc := .3; nn := 1.5;
Eq1 := nn.(diff(f(eta), eta))^(nn-1).(diff(f(eta), `$`(eta, 2)))-(nn+1)/(2.*nn+1).eta.(diff(theta(eta), eta)-Nr.(diff(h(eta), eta))-Rb.(diff(g(eta), eta))) = 0;
Eq2 := diff(theta(eta), `$`(eta, 2))+nn/(2.*nn+1).f(eta).(diff(theta(eta), eta))+Nb.(diff(theta(eta), eta)).(diff(h(eta), eta))+Nt.((diff(theta(eta), eta))^2) = 0;
Eq3 := diff(h(eta), `$`(eta, 2))+nn/(2.*nn+1).Le.f(eta).(diff(h(eta), eta))+Nt/Nb.(diff(theta(eta), `$`(eta, 2))) = 0;
Eq4 := diff(g(eta), `$`(eta, 2))+nn/(2.*nn+1).Lb.f(eta).(diff(g(eta), eta))-Pe.((diff(g(eta), eta)).(diff(h(eta), eta))+(diff(h(eta), `$`(eta, 2))).g(eta)) = 0;
etainf := 10;
bcs := f(0) = ss/Le.(D(h))(0), theta(0) = lambda+aa.(D(theta))(0), h(0) = lambda+bb.(D(h))(0), g(0) = lambda+cc.(D(g))(0), (D(f))(etainf) = 0, theta(etainf) = 0, h(etainf) = 0, g(etainf) = 0;
dsys := {Eq1, Eq2, Eq3, Eq4, bcs};
dsol := dsolve(dsys, numeric, continuation = lambda, output = procedurelist);
Error, (in RootOf) expression independent of, _Z