## 218 Reputation

18 years, 230 days

## copy maple.ini...

1. Install the package by double clicking on the file you downloaded (grtii6.exe). It will extract everything in C:\Grtii(6) directory. Do not change this location.

2. You will see a file called "maple.ini" in C:\Grtii(6). Copy this file into Maple's "bin.win" and "Users" directories.

3. Open Maple and try the command grtw(); If you can see

GRTensorII Version 1.79 (R4)
6 February 2001
Developed by Peter Musgrave, Denis Pollney and Kayll Lake
C:/Grtii(6)/Metrics

it is installed successfully.

## check the paranthesis and use "solve"...

1. Check your paranthesis and do not use {, [, }, ]. Use only ( and ).

2. Name your equation (not necessary but preferable):

eqn:=1+((25.*phi^3-297.*phi^2+1162.*phi-1500.))*(840.+332.*theta+29.*theta^2)/((phi^4-16.*phi^3+89.*phi^2-201.*phi+150.)*(3.+theta)*(28.+11.*theta+theta^2));

3. Use the "solve" command:

result:=solve(eqn=0,theta)

if the equation equals to zero of course.

Please first check the paranthesis carefully.

## The type of the equations...

1. Is the set of equations linear? If it is linear, try Gauss elimination.

2. Are the coefficients symbolic or numeric? If they are symbolic, try to simplify the coefficients first.

3. Pick an equation, find just one unknown in terms of the others and use this expression in the other equations. Then, find another unknown using another equation and use it in the other equations, and so on. Going like this you will end up with a single equation with one unknown. Solve it and do everything backwards to find the rest.

By the way, you can solve only 8 unknowns using 8 equations. The other 8 should be your coefficients.

## launch.ini...

Hi,

There is a file named as launch.ini in bin.win (or bin.x86_64_windows) directory. Open it and add the line

language=en

at the bottom (without #'s) and save. Now try 2D input mode.

## The command is dsolve. You can read the ...

The command is dsolve. You can read the help file using

Let's first try without the initial condition:

and with the initial condition:

I hope this helps.

## A Maple file that may be useful...

This Maple file may be useful:

www.maplesoft.com/view.aspx?SF=19187/laplacelenzvec2.mw

## Try explicit forms...

Try:

x:=x1+I*x2

xconj:=x1-I*x2

y:=y1+I*y2

yconj:=y1-I*y2

etc.

Then you will have two equations associated with the each equation: One for the real part and one for the imaginary part.

## The KM Player with Windows 7...

I use the KM Player with Windows 7 and the following command plays the mp3 file "comeagain.mp3" by launching the KM Player:

system[launch](cat("F:/Program Files (x86)/The KMPlayer/KMPlayer.exe F:\comeagain.mp3"))

**Be careful about the paths of the media player and the sound file.**

## Optimization again...

I also think that you should optimize your code.

- You may think of changing your Newton-Raphson routine to Maple's internal N-R routine. I think it is in the student package.

- Try to reduce the number of loops. If you multiply or add some vectors or matrices, multiply or add them directly, not in some loops. I think this is the first thing you should be thinking of seriously.

- If you have a graphics card with CUDA support you can easily use this property for multiplying matrices. It reduces the operation time remarkably.

## size...

You can also use,

## A workaround...

Thank you Axel and Robert, both your comments are valuable. I found another workaround bu using two algsubs commands in a row.

I first set (k-p*x)=H1 and then I set x*H1=H2. This also solves my problem along with your solutions.

## The solution is here!...

Credits and thanks to Michael from the technical team!

1. Navigate to your Maple installation folder (Start – My Computer – Local Disk (C:) – Program Files – Maple 14)

2. Go to Maple’s bin.win (or the analog) folder

3. Right-click on the file called “launch.ini” and select “Open with...”

4. Choose “Select the program from a list” and click OK

5. Choose a text-editing program (e.g. WordPad) and click OK

6. In the launch.ini file add the following line:

language=en

7. Save the file and launch Maple.

This solved all my problems.

## Solution is here...

Credits and thanks to Michael from the technical team!

1. Navigate to your Maple installation folder (Start – My Computer – Local Disk (C:) – Program Files – Maple 14)

2. Go to Maple’s bin.win (or the analog) folder

3. Right-click on the file called “launch.ini” and select “Open with...”

4. Choose “Select the program from a list” and click OK

5. Choose a text-editing program (e.g. WordPad) and click OK

6. In the launch.ini file add the following line:

language=en

7. Save the file and launch Maple.

## A clue...

Use dsolve command and type y" as diff(y(x),x\$2) and y as y(x).

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