LTPDA Toolbox™

Trouble-shooting

A collection of trouble-shooting steps.

Java Heap Problem

When loading or saving large XML files, MATLAB sometimes reports problems due to insufficient heap memory for the Java Virtual Machine.

Since MATLAB version 2010a can you increase the the heap space for the Java VM in the preferences.
You can change the java heap size by using the General Preferences dialog.

Since MATLAB version R2012b can you access this dialog on the Home tab, in the Environment section, by clicking Preferences.
Select MATLAB > General > Java Heap Memory.
In MATLAB versions earlier than R2012b can you access the dialog with: File > Preferences > General > Java Heap Memory
For older MATLAB versions (2009b) please use the following.
You can increase the heap space for the Java VM in MATLAB 6.0 and higher by creating a java.opts file in the $MATLAB/bin/$ARCH (or in the current directory when you start MATLAB) containing the following command: -Xmx$MEMSIZE

Recommended:

-Xmx536870912

which is 512Mb of heap memory.

An additional workaround reported in case the above doesn't work: It sometimes happens with MATLAB R2007b on WinXP that after you create the java.opts file, MATLAB won't start (it crashes after the splash-screen).
The workaround is to set an environment variable MATLAB_RESERVE_LO=0.

This can be set by performing the following steps:
1. Select Start->Settings->Control Panel->System
2. Select the "Advanced" tab
3. On the bottom, center, click on "Environment variables"
4. Click "New" (choose the one under "User variables for Current User")
5. Enter
  Variable Name: MATLAB_RESERVE_LO
  Variable Value: 0
6. Click OK as many times as needed to close the window
Then edit/create the java.opts file as described above. You can also specify the units (for instance -Xmx512m or -Xmx524288k or -Xmx536870912 will all give you 512 Mb).

LTPDA Directory Name

Problems have been seen on Windows machines if the LTPDA toolbox directory name contains '.'. In this case, just rename the base LTPDA directory before adding it to the MATLAB path.

Problems to execute MEX files

User with the operating system "Windows XP" will get trouble if you want to execute MEX files. This happens if you are useing for example the methods 'detrend', 'smoother', 'lpsd', ...
You will get the following error:

??? Invalid MEX-file 'C:\ltpda_toolbox\ltpda\src\ltpda_dft\ltpda_dft.mexw32':
This application has failed to start because the application configuration is incorrect.
Reinstalling the application may fix this problem.

You can solve this problem by installing the Microsoft Visual C++ 2008 Redistributable Package. This is necessary because all the MEX files are compiled with Microsoft Visual C++ 2008. You can install this package from the LTPDA toolbox or from the official Microsoft web page.

LTPDA toolbox
- Windows 32 bit
- Windows 64 bit
Official Microsoft web page
- Windows 32 bit
- Windows 64 bit

Problems to use external links in LTPDA help

User with a Ubuntu 12.04 LTS OS may have problems to open external links because Firefox needs a much newer libstdc++ library as MATLAB delivers. You can check if this workaround apply to you by typing "!firefox &" in the command window. The should you get the following error massage:

>> !firefox &
XPCOMGlueLoad error for file /usr/lib/firefox/libxpcom.so:
libxul.so: cannot open shared object file: No such file or directory
Couldn't load XPCOM.
firefox: Signal 127

If so then should you use the system libstdc++ library instead of MATLAB's libstdc++ library.

This can be done by performing the following steps:

Identify the location of MATLAB's libstdc++ library path.
You can do this with the linux command "locate -i libstdc++.so.6". MATLAB 2012a habe two libstdc++ libraries (older MATLAB versions have only one libstdc++ library) and the path are:
$MATLABROOT/sys/os/$ARCH
$MATLABROOT/bin/$ARCH
where $MATLABROOT is the installation path of your MATLAB (e.g. /usr/local/MATLAB/R2012a) and $ARCH is the architecture corresponds to yours OS (e.g. glnxa64 ).
Move MATLAB's libstdc++ library to a backup folder.
Use the following command in a ubuntu terminal.
```
cd $MATLABROOT/sys/os/$ARCH
sudo mkdir old
sudo mv libstdc++* old/
```
You should do the steps above for all libstdc++ libraries you find on MATLAB installation path.

MATLAB unresponsive when using doc or web on some Macintosh systems

On some MacOS systems, the call to MATLAB's doc or web (that happen after clicking on the 'Parameters description' link in the help of methods or in call to the methods called toHtml) may lead to MATLAB being stuck. This issue is associated to the "Enable Access for Assistive Devices" setting. Details and proposed solutions are described here:

Mathworks support

Java 7 UnknownHostException

Java 7 throws an error to get the local host information. The error occures with the following command:

>> a = ao(1)

Error using provenance (line 51)
Java exception occurred:
java.net.UnknownHostException: your-machine-name: your-machine-name: nodename nor servname provided, or not known
at java.net.InetAddress.getLocalHost(InetAddress.java:1438)
Caused by: java.net.UnknownHostException: your-machine-name: nodename nor servname provided, or not known
at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:866)
at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1258)
at java.net.InetAddress.getLocalHost(InetAddress.java:1434)

The workaround is to add the name of the machine to your ‘/etc/hosts’ file. For example add the following line

127.0.0.1    your-machine-name

Additional 3rd-party software

Introducing LTPDA Objects