## Undefined...

While using Maple 10 at school I ran into an error when trying to plot a spacecurve within a 3D plot. When I enter: > A:=spacecurve([2*x,0,0],t=0..1); I get: A := PLOT3D(CURVES([[undefined,undefined,undefined],[undefined,undefined,undefined].. That take up half the screen. If I try to plot this, there is no curve on the plot, but I can see the axes. WinXP SP2 1024Mb RAM (I think) Nvidia Ti-4200

## tildes all over again...

I want to ask about a small problem. I will present a paper at a conference in February. Because it involves time consuming calculations of numerical solutions for several onerous systems, I will do the calculations at home before the talk, save the results, and show the output to the conference. The folks attending the conference are not necessarily Maple Folks, so I do not want to have to explain the tilde after characters for which I have made assumptions. Of course, I know about

interface(showassumed=0);

After making the calculations here at home, traveling to the meeting, opening the file to make the presentation then, alas, the tildes are back again. Try this.

> assume(a, real):
> interface(showassumed=0):
> equa:=a^2+a-1;

Run this file. No tilde. Close the file saving the output. Open the file. There is the tilde after each “a".

My question:is there some way to make the tilde stay gone when I save such a file and reopen it without recalculation the worksheet?

## Using the Mathematica Translator...

Does anyone know how to use the Maple workheet "Mma" which is supposed to translate Mathematica notebooks into Maple? I got Mma from the Maple site (http://www.maplesoft.com/applications/app_center_view.aspx?AID=1483&CID=9&SCID=63) Is appears easy. Initialize the process with the commands interface(warnlevel=0): interface(displayprecision=4): with( MmaTranslator ): The give the tranlator the location of the Mathematica notebook with FromMmaNotebook( "C:/Notebooks/mmaSampler.nb" ); Even though I've checked the Matematica notebook for accuracy, All I ever get are error messages.

## Maple10 doesn't start anymore...

Hi all, I'm a new user so...you'll forgive me if I've chosen the wrong forum. That's my problem: I've used Maple 10 3 or 4 times since the installation, but the last time I've tried to start it, the window was completely GRAY; after about a minute an error message appeared saying something about a 'peripheral error' and 'restart the computer to restore the system' (...sorry for bad translation from italian), the interesting thing is that the system has changed its graphical settings about the monitor resolution (800*600) and colors (I think 4 or 16). An other information... I noticed that a txt file was created just in that time and placed into maple directory: 'hs_err_pid1136.txt'; opening it you can read 'An unexpected exception has been detected in native code outside the VM.

## Non Linear System and PID Controller...

Hi guys ;) I have a question. Is it possible to apply a PID controller with the following parameters(P=6,I=4,D=0.02)to a Non Linear System described with the differentiate equation like this mk*diff(x(t),t,t)+kfv*diff(x(t),t)-(ki^2*u(t)^2*kc)/(mk*(x(t)-x10)^2)-mk*g=0 or in the second form, as two differentiate equations like dx1 := (x1,x2) ->x2; dx2 := (x1,x2) ->((u*ki)^2*kc)/(mk*(x1-x10)^2)-g*mk/mk-kfv*x2/mk; without linearisation in operating point, where u - is input variable, x - position, dx/dt - velocity, d^2x/dt - acceleration ? Thanks for your help.

## Delete folder/file in Maple 10...

Delete a file or folder that I no longer want to retain.

## Time delay in transfer function...

Hi. I have a transfer function like this one: y:=(2.5)/((8*s^2+6*s+1)*s); and I can make inverse Laplace transformation in time and plot it by: y1:=invlaplace(y,s,t); plot(y1,t=0..25); I try it also with time delay in transfer function but it doesn`t work. y:=(2.5*exp(-1.5*s))/((8*s^2+6*s+1)*s); > y1:=invlaplace(y,s,t); > plot(y1,t=0..25); So i find a solution in differential equation and make an algorithm to convert transfer function to differential equation. ode := 8*(diff(x(t), t, t))+6*(diff(x(t), t))+x(t) = 2.5*Heaviside(t-1.5); ics := x(0) = 0, (D(x))(0) = 0;

## 2 questions......

Hi Maple's experts! I have two questions related to "iso-product" lines (in economics): 1. I draw the following graphs F:=plot3d( min(x,30*y), x=0..20, y=0..20): G:=plot3d( min(20*x,y), x=0..20, y=0..20): display({F,G}); a) How could I graph the contourlevels of the "combined" graphic of F and G? b) Obviously, the contourlevels are not convex.. it would be possible to "convexify" that?. 2. How could I do the same a) and b) if F:=plot3d( min(x,30*y), x=0..20, y=0..20): G:=plot3d( min(20*x,y), x=0..20, y=0..20): H:=plot3d( 3*(x*y)^(1/2), x=0..20, y=0..20); display({F,G,H});

## Q about Open Maple API...

I want to compile the appended code snippet from HelpExamples.c into a DLL using MSVC6 and added C:\Programme\Maple10\extern\include as well as C:\Programme\Maple10\bin.win as pathes to the project. After compiling I get the following error message for linking: Linking... Creating library Release/MapleAPI.lib and object Release/MapleAPI.exp MapleAPI.obj : error LNK2001: unresolved external symbol __imp__ToMapleString@8 It seems that i miss an import library - what should I do (except having a break for some more coffee)? Sh... upload does not work for 2 kB - exceeds maximum file size

## dsolve...

I am trying to solve an equation and I receive this: "Error, (in fproc) unable to evaluate expression to hardware floats" Please help

## Rotate Text...

Hello, is it possible to rotate a text so that it appears upside down or any other angle? Thank You very much! Corpuscowboy

## How to hide input statements in document mode?...

My last question was answered so quickly, I thought I would try again:-) I am developing documents for my class in document mode. I want to be able to set the examples up so that if they change the example, then maple will update all of the subsequent calculations connected to it. I think I have that pretty well figured out. My problem is that the flow of the document is interrupted by the necessary maple commands to produce the required output. For example, I have the code "subs(x=-4,(4.2.3))" that is executed to give an equation. It shows the code and then the equation on the next line. I would like to hide the code.