Undefined functions while using struct and optim packages in Octave

If you have encountered errors like these in octave:


error: 'cell2fields' undefined near line 939 column 11
error: called from
    __nonlin_residmin__> at line -1 column -1
    __lm_svd__ at line 191 column 9
    __nonlin_residmin__ at line 1128 column 21
    nonlin_curvefit at line 83 column 18
    nlinfit at line 169 column 18

OR these

error: '__collect_constraints__' undefined near line 152 column 7
error: called from
    __nonlin_residmin__ at line 151 column 48
    nonlin_curvefit at line 83 column 18
    nlinfit at line 169 column 18



mean that NOT all the functions in the packages struct or optim have been correctly imported into Octave.


istread of importing the single folders in the Octave's path:


addpath('/home/eddie/octave/struct-1.0.14') % NOT ENOUGH!!!
addpath('/home/eddie/octave/optim-1.5.2')   % NOT ENOUGH!!!


just use the pkg command:


pkg load struct ;
pkg load optim ;

That's it. Happy scientific programming :)

H-264 is magic

A very interesting reading about H-264

https://sidbala.com/h-264-is-magic/

Windows Update Error 8024402C

1. Go to Administrative Tools/Services and find the Windows Update service. Stop it.
2. Go to C:\Windows\ and rename the SoftwareDistribution folder to something like SoftwareDistribution.old
3. Restart the Windows Update service.
4. Click the Check for Updates button on the Windows Update screen.
5. Windows will perform the check - it may take some time, so leave it running. Eventually it will successfully complete.
6. You can then delete the SoftwareSistribution.old folder.

Source:
http://www.sevenforums.com/windows-updates-activation/218303-windows-wont-update-error-8024402c.html

bash history with timestamps

This is definitely something useful!
How to attach timestamps to the history of the bash commands?
Simple:  just set (in the way you like to have your time format) the bash variable HISTTIMEFORMAT

For example to have the format: day/month/year - hours:minutes:seconds" type this:

export HISTTIMEFORMAT="%d/%m/%y - %H:%M:%S: "

and then just run history

That's it!

Source
 stackoverflow

"Server is either down or too busy to respond" with AppStatusCheck

If you got this problem (and your server IS up and running!) it means you haven't set the correct JDBC driver in your AppStatusCheck.tra file.

The path to the JDBC driver (for example ojdbc6.jar) must be set in the property

tibco.class.path.extended

That's it!

What every programmer / computer scientist should know about X

Here are some useful references for Programmers/Computer Scientists.

What every programmer / computer scientist should know about X where X is:

• Memory: What Every Programmer Should Know About Memory by Ulrich Drepper (2007) Recommended by Scott Meyers. Links: pdf, pdf

 

• Floating point: What Every Computer Scientist Should Know About Floating-Point Arithmetic by David Goldberg (1991).  Recommended by John Farrier at CppCon 2015. Links: pdf, pdf,

More to come... ;)

Linux: VMWare tools problem: "host software version may not be compatible with the upgrader"

If you run vmware-tools-upgrader-64 to install/upgrade your VMWare tools on your VM and you get the error:


Starting Tools Upgrader
RpcIn: Registering callback 'reset'
RpcIn: Registering callback 'ping'
RpcIn: Registering callback 'Capabilities_Register'
RpcIn: Registering callback 'upgrader.run'
RpcIn: Registering callback 'upgrader.cancel'
HgfsChannelGuest_Init: app tools-upgrader rpc = 0 rpc cb = 0.
HgfsChannelInitServer: Initialize Hgfs server.
HgfsChannelInitChannel: Init channel return 1.
HgfsChannelGuestBdInit: guest initialized.
RpcIn: Registering callback 'f'
Upgrader: To VMX: tools.capability.hgfs_server tools-upgrader 1
Rpci: Sending request='tools.capability.hgfs_server tools-upgrader 1'
Rpci: Sent request='tools.capability.hgfs_server tools-upgrader 1', reply='', len=0, status=1
Upgrader: To VMX: upgrader.setGuestFileRoot /tmp/vmware-root/296113e0/
Rpci: Sending request='upgrader.setGuestFileRoot /tmp/vmware-root/296113e0/'
Rpci: Sent request='upgrader.setGuestFileRoot /tmp/vmware-root/296113e0/', reply='Failed', len=6, status=1
RPC greeting failed: Host software version may not be compatible with the Upgrader.
Setting temp directory root failed.
Upgrader failed initialization.
Upgrader: To VMX: tools.capability.hgfs_server tools-upgrader 0
Rpci: Sending request='tools.capability.hgfs_server tools-upgrader 0'
Rpci: Sent request='tools.capability.hgfs_server tools-upgrader 0', reply='', len=0, status=1
RpcIn: Unregistering callback 'f'
HgfsChannelGuest_Exit: app tools-upgrader rpc = 0 rpc cb = 0 chn = 7F42C8489060.
HgfsChannelExitServer: Teardown Hgfs server.
HgfsChannelExitChannel: Exit channel returns.


it means you need to do some extra work to install the VMWareTools ;)

The solution is to unpack manually the tar file and run the installer:


tar xvf VMwareTools-10.0.10-4301679.tar.gz # actual version could be different

cd  vmware-tools-distrib

run (as ROOT) the command

 ./vmware-install.pl


Done!