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Dear Community,

How could I specify a list of random colors using some kind of an RGB function, which then could be used in another command for coloring? I think of something like this:

myColors := [ seq( RGB ( [rint(0,255) , rint(0,255) , rint(0,255)] ) , j = 1 .. 20 ) ] :

which does not work of course :-)  This should produce me a list of 20 random colors.  What would be the right RGB color function?

Tx for the kind help in advance

best regards


In plots made with 'complexplot3d', Maple uses by default a color wheel for the argument of complex numbers in which positive numbers are painted cyan and negative numbers are red. Is there a way to change this to the other common convention (i.e. cyan negative and red positive numbers)?


Any help would be really appreciated, as it's not convenient to have graphs made with different conventions in the same document and I wouldn't want to remake all the ones I already have.


I would like to know if it is possible to change the color for the result from blue to black or red. Maybe by editing the text that state the colors.

And the same goes for the color palette, can I make my own colors in the color palette text. It should work by default.




I am calculating the temperature of a rod which has one end at the temperature T1 and the other end at T2 and it's evolution. We were already given the formula for the numeric calculation and after a short while I managed to obtain a small program that would calculate the temperature of each segment of the T(x,t) grid:

>restart: with(plots): nx:=20: tmax:=50: T1:=1: T2:=10: L:=1: k:=1: rho:=1: cp:=1: chi:=k/rho/cp: h:=L/(nx-1): t:=1e-3:
>for k from 0 to nx do T(k,0):=T1 od:
for w from 1 to tmax do
T(0,w):=T1: T(nx,w):=T2:
for q from 1 to nx-1 do
od: od:

With L the Length of the rod, t and h the time and space increment [h=L/(nx-1), where nx is the number of intervals we divide the x-axis, although I'm not quite sure the '-1' should be there], chi a constant different for each rod and tmax total time we want to calculate. The formula from the 5th line was given to us, so in that part there is no mistake.

Up until here everything works perfectly fine.

Now I want to be able to draw this and here is where all the problems appear. I want to draw this in a 2D graph with position in the x-axis and time in the y-axis. I have tried "densityplot(T(x,y),x=0..nx,y=0..tmax)" which would seem to be the logical whay to continue this. As I understand it, this plot would draw an nx times tmax grid and colour the whole plpot black-white acording to the maximum and the minimum value (as shown in the maple help page of this plot).

However, when I do this a black square appears (or red if I add colorstyle=HUE). I have tried a lot of things and none seemed to work.

I would also like to be able to draw the isotherms on the plot but that is secondary.


I am pretty new to Maple. I have studied the most basic things but don't really understand the whole complexity of this program. Thanks a lot in advance and forgive my faulty english,



This Application uses the xrite color checker to obtain Forward and Color Matrices as defined by Adobe.

It compares the camera gamut based on the above matrices to the 1931 Standard Observer using LEDs.




I would like to scale the last KernelDensityPlot in the attached worksheet to overlay with the Histogram above it.  The result would look like the 3rd plot in the worksheet, except the y-axis ranges would match.




Hi Maple People


# Some Maple code
x:= Vector(10):
y:= Vector(10):

for z from -5 to 4 do
   x[z+6]:=z^2 + 40:
   y[z+6]:=z^2 + z + 41:
end do:





In a post of April 15, 2013 by Kitonum, the procedure named Picture accepts a list of polygon segments, creates a plot of these as a 2D polygon's boundaries and fills the polygon with a color.

The code below attempts to modify Picture to produce a 3D filled polygon in a plane parallel to the xy plane.

When invoked by the code below the procedure, the filling color conforms to the straight line boundaries but overflows the curved, parabolic boundary. How can this be corrected?

Picture:=proc(L, C, N::posint:=100, Boundary::list:=[linestyle=1])

 local i, var, var1, var2,e, e1, e2,e3, P, h ;

 global Q,Border;

 for i to nops(L) do    

#` set P`[i] = list of points for each segment.    

#` for a segment defined as a list of points, P[i] = the segment's definition`

#` for a curve definition, approximate it with a list of [x,y] points of its function evaluated at N even intervals in its

# range`  

  if type(L[i],listlist(algebraic))  then P[i]:=op(L[i]);   else  

  #` for curve def'n, set var = def'n and h= `(variable range)/(2)

  var:=lhs(L[i,2]);  var1:=lhs(rhs(L[i,2]));  var2:= rhs(rhs(L[i,2])); h:=(var2-var1)/(N);

  #` for function def'n, set e=function`

 if type(L[i,1], algebraic) then  e:=L[i,1];

  #` for polar function r=f(t) create N values of the [cos*r,sin*r] i.e. the equivalent [x,y] values for r valued at N even

  # divisions of its range`  

 if nops(L[i])=3 then P[i]:=seq(subs(var=var1+h*i,[e*cos(var), e*sin(var)]), i=0..N);  else

    #` for non-polar function y=f(x) create N values of [x,y] for x values at N even divisions of its range`  

 P[i]:=seq([var1+h*i, subs(var=var1+h*i,e)], i=0..N)  fi;  else

 #` for parametric function [f`(t),g(t)] create N values of [f(t),g(t)] for t values at N even divisions of its range.

     e1:=L[i,1,1];  e2:=L[i,1,2];

#` P`[i]:=seq(subs(var=var1+i*h,[e1, e2]), i=0..N):

 P[i]:=seq([subs(var=var1+i*h,e1), subs(var=var1+i*h,e2),0], i=0..N) fi; fi; od;  #`  MODIFIED FOR 3 D `[f(t), g(t), 0] 

  Q:=[seq(P[i], i=1..nops(L))];

 Border:=plottools[curve]([op(Q), Q[1]],  op(Boundary));

     #` the shaded figure is a polygon whose vertices are Q, whose interior color is C`  

 #` return a list of the polygon and its border`

   [plottools[polygon](Q, C),  Border];

 end proc: 

L := [[[0, 0, 0], [0, 1, 0]], [[x, x^2+1, 0], x = 0 .. 2], [[2, 5, 0], [2, 2, 0]], [[x, x, 0], x = 2 .. 0]]:

plots[display](Picture(L, color = yellow), axes = normal, scaling = constrained)

Dear all,


I am tryong to use the density plot for the first time.

Following maple instructions in maplsoft, I type 


but I get the error below:

Error, (in plot/options2d) unexpected option: colorscheme =["π™±πš•πšžπšŽ","π™Άπš›πšŽπšŽπš—","π™Ύπš›πšŠπš—πšπšŽ"])

It actually works with one color, but not with colorscheme!


Is there a way to permanent change the color of the output in maple?

Well, long story short. Sat in class, got bored. Began thinking of how to plot different figures in maple.
This eventually leading to that of a rainbow. Anyone got a formula or something i can use to create one? :-)
Thanks ahead. :)

When assigning a color to a given wave length I initially used ColorTools WavelengthToColor. Acer commented that this wasn't the most accurate. I looked into this a little further and it seems there could be a better result. The attached document compares some different ways of assigning colors to wave lengths. 

Warning- The CIEDE2000 computation for deltaE is very slow. I think this is because of the hue angle calculations which use piecewise a lot. The CIE94 delta E method produces nearly the same result and takes minutes instead of hours.



 I think I could speed up my calculation if I could find the position of the minimum element of an Array similar to FindMinimalElement of a list. 

I created my own atan2 function (similar to Excel). If there were a built in Maple equivalent perhaps it would be faster? I didn't see any such function.

The downloaded worksheet below displays 3 points on the unit sphere which define a solid angle with a triangular face. The sides of the solid angle's are red arcs on the surface of the sphere and red radii which outline the planar sides within the sphere.

Three questions:

1. Is there a way to make the surfaces of the solid triangle more apparent by filling them with color?

2. Is there a way to calculate the area of the face on the surface of the sphere?

3. Is there a way to calculate the volume of the solid triangle?


Download Mechanics;

How can I do a color inversion on a jpg image in Maple?

Hi, Everyone.

I'm trying to figure out how to make a graph (actually a "line") change color based on certain criteria so I can create a Maple Application.

I've figured out the following, which indicates the sign of the graph by the color, but it's way more complicated than it ought to be.

It's also not robust as I need it to be, this happens to depend on the zeros occuring at integer values.  I could deal with that on a case by case basis, but not for something automatically.

I'm at a loss; maybe I'm not Googling the right things... maybe Maple can't do this (although I'd heard color tools were being added in Maple 16).

Does anyone have any suggestions?

Thanks In Advance!


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