Sum every fifth term in an expression...

Hi... I have a long-expression, which I have abbreviated here. I want every 5th term summed. Included is my code, but I need the unassign command (after point 12) for it to work. The problem is when I unhash and insert this unassign('s','X[4]') command into my actual Table of Records procedure, Maple protests. it gives a cryptic: " Error, `(` unexpected " .
How can I modify the original code to sum every 5th term as efficiently as possible as the thing is a 4000 term expression which I later need to numerically integrate?

sum_every_5th.mw

Round decimal up or down...

Hey

Does Maple have the equivalent of the MROUND Excel command?

Or can someone kindly make a procedure.

eg

MROUND(1986,10)=1990

MROUND(492,5)=490

thanks!

Strange Optimization Output...

Hello everyone

I observe the following "strange" case and I am wondering if I am missing something. So, any insights are more than appreciated. The case is the followin:

When I use

with(Optimization):
Interactive(x + y, {x = 0 .. 1, y = 0 .. 1, 1 <= x + y})

I get: objective =1, x=y=.5

However, If I run

with(Optimization):
Minimize(x + y, {x >=0,x<=1, y>=0,y<=1, 1 <= x + y})

then I get: objective =1, x=1, y=0

Why there is such a difference? Because of there are multiple solutions?

How to Plot a Colored Surface Under plot3d That Is...

Hi MaplePrimes team,

I want to create two 3d surfaces with plot3d command in Maple, one of which represents a light-emitting diode (LED).

For that, my idea is simple: Just to disable the shade on a specific surface (representing the LED-like) among other surface. So, whatever the direction of the light, the LED surface keeps a constant luminosity.

Unfortunately, the glossiness = 0 option is still dependent of light direction.

I looked at all the options for plot3d and display commands, but I couldn't find anything for disable light on special surface.

Maybe in PLOT3D command?

If not, is there an option to add a second light source?

Simple example I would like create:

- 1. A surface with regular light:

BALL := plot3d(<cos(t)*cos(s), cos(t)*sin(s), sin(t)>, s = 0..2*Pi, t =-Pi/2..Pi/2, color = "Blue"):

- 2. An illuminated surface representing the LED:

LED := plot3d((<2 + cos(t)*cos(s), cos(t)*sin(s), sin(t)>, s = 0..2*Pi, t =-Pi/2..Pi/2, color = "Yellow", What option to insert?):

Then, the assembly will give:

display(BALL, LED);

My Advanced Applications Tests in Maple

Figure 1: Aisle LED light and LED-screens of first-class seats in an illuminated cabin on board of an aircraft.

Figure 2: Here is the problem in the darkness. The aisle LED light and LED-screen must be stay constantly illuminated for any direction of light.

To better understand my objectives, here is another image using lights. Note that the LEDs (pale yellow strip shapes) stay constantly illuminated whatever the daylight and therefore allowing the aircraft to be visible.

Figure 3: Exterior lighting systems and dazzling jet engine afterburner of a military transport aircraft concept.

Best.

Guy.

How do I print (3*Pi)/10 instead of Maple's (3/10)...

I need to get more tickmarks in my plots by reducing the size of fractions produced by Maple.
For example, instead of (3*Pi)/10, Maple gives me (3/10)*Pi. Any help would be appreciated.
I can actually convert all there Maple numbers to fractions, but Maple will not accept these conversions as tickmarks.
Thank you.
mapleatha

How do I output sin(x) in red in this title?...

I need tto change the color of a word or a math expression inside the title of a Maple plot.
For example, I need to have sin(x) in red in this axes plot:

AX:=plot([[x,0,x=0..Pi],[0,y,y=0..1]],color=black,thickness=3,title=typeset("\nLeft Riemann Sum for the Function:\n",sin(x), "on the interval ", [0,Pi]\n),titlefont=["Arial",25]):

How do I do it?

Thank you!

mapleatha

Setup Differential Equation into a Matrixform...

I'm practicing with matrices in Maple, but I have a question. My question is, how do I set up the differential equation system on matrix form x '(t) = Ax (t) + B?

Here are the equations:

x'1(t) = x1(t) - x2(t) - 3

x'2(t) = 12x1(t) - 8x2(t) + 4

I've been looking around for some help sources, but the only one I could find is this. I tried to set it up like that, but didn't work, it gave me an error.

How should I set it up (using Maple commands)?

How do some plot commands evaluate complex express...

In this worksheet, how do the several successful plot commands evaluate the complex expression being plotted, and why do the unsuccessful plot commands fail to do so?

Plot_complex_expression.mw

Integration of spline...

I am trying to do the integration on the picture (int1). V,omega,theta,rhotræ,ix,iy,ixy,E,R are constants. a(r),å(r),FL(r),FD(r) are splines. It seems to run forever without any error. I have tried a simpler version to figure out if the problem has to do with the splines or the arctan. They can run independently but not when combined. (int2). I use an i7 6700k. I am fine with an aproximated answer within a couple %.

How do I solve a equation ln in Maple?...

Hi!

How do I solve a equation ln in Maple:ln.mw

How to output "(mol/L)^2" instead of "L^2/mol^2"?...

Hello

When doing chemistry in Maple, I want to be able to do my calculations with units.

Maple does not support the unit [M] (molar concentration), so I have to manually type the unit as [mol/L].

That is not a problem in itself, but I have encountered som issues with Maple's own formatting of the units.

For example, in the attached document I want the output unit to be (mol/L)^(-2). However, Maple automatically formats it as

It even does the same thing in the "Maple Math" here on MaplePrimes - Here I try to type (mol/L)^(-2):

So does anyone know a way to avoid Maple's auto-formatting of the output, or is there a way to customize it so I get my desired output?

I have attached the document with some screenshots in it: chemistry_units.mw

// Frederik

How can I play a tone in Maple?...

I am investigating the history of scales and temperament in western music. I would like to be able to play a tone of a given frequency in Maple, and then a sequence of tones to make a scale, and then a collection of tones to make a chord. I found the Play command  in the online help screen for Audio Tools, but can't make it work. I don't get an error message, but neither do I get a sound.

How to set a range to a function containing a vari...

I have the following equations and plot in Maple, but I would like for Maple to only consider positive values of k, but I cannot find a way to do this as k is dependent on x. Is there any way to do this either in the code for k, or in the code for the plot?

Corrupt Maple file help!...

Hello,

Im having trouble fully opening the contents of my maple file. Only half of the doucment is showing up.

I get the following message: "There were problems during the loading process, Your worksheet may be incomplete."

There is also no bak. file available.

matOpgaver_1.mw.zip