Hello friends,

I have an image in black and white and I wanted to compute and plot the intensity distribution histogram of it. So I did it with the command PlotHistogram, here's the output:

> PlotHistogram(Lena, 256)

I established the number of buckets to 256 but I don't see them at the x-asis, and I would like to see them for clarity as I don't understand the scale that is used by default. Could you help me achieve this and maybe also understand the scale used by default?

Thanks a lot.

I use nprintf to create greek characters as strings so that I can print them using printf.  But here is the strange behavior:

gk_Omega1 := nprintf("#%a", 937);
gk_Omega2 := nprintf("#%a", 937);

printf("%s %s", gk_Omega1, gk_Omega2);

does not print the same.  The gk_Omega1 is fine, but the gk_Omega2 prints "#937" instead of the the greek Omega character.

Does anyone see why this is?

Thanks, David
 

Can anyone look at this worksheet, and explain why maple seems to complicate an easily evaluated integral?

Hyper.mw

What kind of options do I have regarding printing a document to pdf?

Even though the document I have looks nice on the screen, it doesn't fit to a A4 pdf page.

Are there any scaling options, or fit to page anywhere which I did miss?

Any idea of how to import necessary libraries for use in Maple Player?

This question may be a little dumb, but how can I calculate the resultant of two homogeneous polynomials with two variables according to these variables? Say resultant(f,g,{x,y}), where f(x,y) and g(x,y) are homogeneous polynomials with degree m and n, respectively. Any help would be greatly appreciated!

Dear all, 

Yesterday I asked a very similar question, but i thought about it and found a different way to re-phrase my question:

Given a plot with three dependent variables that depend on one independent variable, how can I extract this data into a .xls (or .dat or whatever) file for re-use in Maple later on? The .xls will have to have 4 columns: the first for the independent variable and the next three for the dependent variables.

Find my worksheet here: worksheet.mw

I managed to write a program that extracts the data into a .dat file, but with only two columns. 

The reason that I want to do this is because I want to re-use the solutions to the variables and the derivatives in a different equation (for plotting). For example q(z) = ( diff(h1(z),z)+ diff(h2(z),z)+ diff(h3(z),z))/(h1(z) +h2(z) +h3(z)), and then z versus plot q(z). Any alternative suggestions would be helpful.

Hi, I am trying to integrate a lengthy-expression but maple does not give a result and got hanged even after waiting 1 hour and more, pls help me to handle this or is this any other way to get a result?

Help_of_Integration.mw

Test3.mw

Would anyone tell me how should I write a and b here for u(x) and v(x)?

Here the code for BVP, but there is a singularity how to avoid it

a:=-0.1:alpha:=0.1:
dsys:={diff(u(r),r,r)+(1-alpha)/r+r^(alpha-2)*diff(u(r),r)=a};

res1:=dsolve(dsys union {u(-1)=0,u(1)=0},numeric,output=listprocedure);

plots[odeplot](res1,[[r,(u(r))]],-5..5,axes=boxed,tickmarks = [3, 2], color = black, thickness = 1, linestyle = solid, titlefont = [Helvetica, roman, 18], labeldirections = [horizontal, vertical], labelfont = [Helvetica, roman, 24]);

Hi all,

Look at my pretty plot.  It is defined by

x=sin(m*t);
y=sin(n*t);

where n and m are one digit positive integers.

You can modify my worksheet with different values of n and m.

pillow_curve.mw

pillow_curve.pdf

The name of the curve may be something like Curve of Lesotho.  I saw this first in one of my father's books.

Regards,
Matt

How I can show function w, on the 3d surface?

I want to show w (a function that shows mode shape or shows boundary condition) on the surface of the following plot3d?

This function changes the coordinates of some points and creates a different shape. this behavior occurs when geometry experiences some vibrational behavior.
Thanks

plot.mw

Hello, 

How can I solve this equation in Maple?

Please help me?

Dear all,

I have 3 ODE's that I solved with the use of a for loop that cycles through different IC's. The purpose of this is so that I can compare the solutions with different IC's. I have three dependent variables (h1(z), h2(z), h3(z)), and one independent variable (z). The loop that I created looks like this:

_Omega_r := 10^(-5);
n := 10;
for i from 0 to n do:
    h10[i] := 1-0.16666667e-1*i;
    h20[i] := 1-(.7*0.16666667e-1)*i;
    h30[i]:= 3-h10[i]-h20[i];
    ans := dsolve([eq2, eq3, eq4, h1(0) = h10[i], h2(0) = h20[i], h3(0) = h30[i]], {h1(z), h2(z), h3(z)}, numeric, output = listprocedure);
    h1_sol[i] := rhs(ans[2]);
    h2_sol[i] := rhs(ans[3]);
    h3_sol[i] := rhs(ans[4]);
    print(i);
end do

Here, h10[i], h20[i] and h30[i] are my initial conditions. I use h1_sol[i], h2_sol[i] and h3_sol[i] to make plots of the solutions:

I make two different types of plots - one type has only the different solutions for h1(z) with all initial conditions:

h1plot := plot([seq(h1_sol[i](z), i = 0 .. 10)], legend = [h1(0) = h10[0], h1(0) = h10[1], h1(0) = h10[2], h1(0) = h10[3], h1(0) = h10[4], h1(0) = h10[5], h1(0) = h10[6], h1(0) = h10[7], h1(0) = h10[8], h1(0) = h10[9], h1(0) = h10[10]], title = "z versus h1(z) for different initial conditions", labels = ["z", "h1(z)"]);

And the other uses one set of initial conditions, but all three h1(z), h2(z), h3(z):

allplot1 := plot([seq(h1_sol[i](z), i = 2), seq(h2_sol[i](z), i = 2), seq(h3_sol[i](z), i = 2)], title = [typeset(h(z), " versus ", z, " (case 2)")], labels = [z, h(z)], legend = [typeset(h[1](z), " with ", h1__0 = h10[2]), typeset(h[2](z), " with ", h2__0 = h20[2]), typeset(h[3](z), " with ", h3__0 = h30[2])]);

Now, all of this works wonderfully. I managed to do everything I wanted. Except that I have been struggling figuring out how to extract the data from the plots into a .dat file into different columns. With the code that I did write, if I use it on the first plot, I end up getting 2 columns, one for z and one for h1(z) (for example), but there should be 11 columns (one for z and 10 for h1(z) with different initial conditions). How would I go about to extract the data of multiple plots into one .dat (or .xls, or .csv or whatever) file? What I did:

write := proc (plotname, filename)
    local fd; fd := fopen(filename, WRITE, TEXT);
    writedata(fd, convert(op([1, 1], plotname), matrix));
    fclose(fd);
end;

write(h1plot, `zvsh1GR.dat`)

Alternatively, if there is a way to use the solution in Maple directly without extracting first (I need to use the solutions for h1(z), h2(z), h3(z) to plot different equations that are dependent on these variables), that would be great. For example, I would like to use these three variables in an equation that uses both the derivatives of all three the variables and the variables themselves as is. For example:

And then I want to plot q(z) vs z.

I'm sorry if this is a lengthy question (or one with a simple solution) - I am still learning Maple.

My Maple file:
Solving_GR_f(R)_ne_2.maple

Maple worksheet: Solving_GR_f(R)_ne_2.mw

Hi, does anyone help me to solve some matrix question in maple. pls have look on my worksheet

Help_Matrix.mw