H5Labview and 1-D arrays

The current version of h5labview can completely crash Labview 2013 SP1 when using 1-D arrays.

What I do to fix this is insert the “Build Array” into my 1-D array just before it hits HDF5 Write Data. On the Read Data, to get a 1-D array again, you can use Index Array with the first row index input as 0.

Ralink RT2800 Warning TX status “fix”

I have some of the ubiquitous USB Wifi sticks with a chipset using the Ralink rt2800 driver. I noticed that while it works fine, I got a lot of dmesg errors like:

rt2800usb_txdone: Warning – Got TX status for an empty queue 2, dropping
rt2800usb_entry_txstatus_timeout: Warning – TX status timeout for entry 14 in queue 2

I’m not a big fan of dozens of dmesg logs per second, so I quickly found this answer that worked for me:

sudo iwconfig wlan1 power off

which according to man iwconfig disables power management. When I’m hanging out with a coffee can Wifi antenna, I’m not interested in saving a few mW so this seems a harmless choice. Note I think you’ll have to type it again after reboot or logoff.


installing LLVM-Py and Numba on Ubuntu 14.04

Note, for most users I would recommend using Anaconda Python rather than fiddling with the steps below, which are OUT OF DATE



OUT OF DATE procedures follows

You need LLVM 3.3 (as of Numba 0.14–thanks for comments from ThyMythos and Raul). As of July 2014, LLVM-Py will not work with the default LLVM 3.4 in Ubuntu 14.04.

sudo apt-get install llvm-3.3-dev python-pip python-dev

Now we install LLVM-Py:

sudo LLVM_CONFIG_PATH=/usr/bin/llvm-config-3.3 pip install llvmpy

Now you can run the tests (optional)

python -c "import llvm; llvm.test()"

Finally install Numba with

sudo pip install numba

Fixing SSH Access Denied for Github

Github suggests that you use the SSH Agent, but even that may not work when you have a lot of SSH keys. You need to setup your ~/.ssh/config file so that SSH to github.com uses the correct SSH Public Key the first time. Here’s how.

nano ~/.ssh/config

and add the lines

Host github.com
        Hostname github.com
        User git
        Port 22 
        IdentitiesOnly yes
        PubKeyAuthentication yes
        IdentityFile ~/.ssh/MyGithubKey

where MyGitHubKey is the key you created following the process (without ssh-agent)

Then switch your remote URL to SSH

Very pleased with Lenovo warranty service

My corporate X220 had the space bar get slightly intermittent after 4 years of hard use and abuse. Naturally the corporation had the maximum warranty coverage, but I didn’t want to have someone manhandling my computer.

Instead, a few minutes on the phone with their Atlanta, Georgia tech support center saw me getting a Next-Day Early Morning express shipped keyboard to my office, so I can change it myself. That is excellent. It probably cost Lenovo more to ship the keyboard than the keyboard itself costs them.

10 years ago I bought my last Dell computer, a nearly $3000 laptop, and the speakers failed after about two months of use, and they sneered at me as if I was blasting death metal music instead of teleconferences. I have heard more recent reports of the same Dell attitude on speakers.
OK different problem, but entirely different attitude from Lenovo tech support.

Although I build my desktops myself, when it comes to laptops I’ll still be looking to Lenovo.