Thursday, October 29, 2015

Using Apache Zeppelin for Spark, SparkML and SparkSQL

Apache Zeppelin[1] is quite a handy tool for exploratory analysis of data using Spark, SparkML and SparkSQL.

Sample Visualization in Apache Zeppelin generated using SparkSQL:

Create RDD, dataframe and register as a temp table:
Query your data using SparkSQL:
Use SparkML for analytics:

Once the Spark SQLContext has the data, Zeppelin can be used to visualize the data.
[1] Apache Zeppelin:

Monday, October 26, 2015

Deep Learning: Identification of Fruits Using Digits, Caffe Framework

Image classification using Neural Networks is a very interesting topic. During my bachelors,  I had a glimpse of Neural Networks - where I specifically worked on "C" code to convert hand written signatures into features that could be fed into the neural networks.

Following is work to take open datasets and classify fruits.

Classification of Orange using the model developed using Digits 2 and Caffe Framework.


  1. CUDA: 7.0
  2. Caffe framework [1]
  3. NVidia GeForce GTX 860M with 640 cores
  4. NVidia Digits 2


  1. Fruit DataSet [2]  (30 categories)
Digits does image classification, with 25% of the images are set for validation.

After many modifications and using AlexNet[2], I have received an accuracy of 60%. Anything beyond this has lead to overfitting. Overfitting is part of Convolution Neural Networks. To avoid over fitting, a large amount of images needs to be available.

I posted on multiple forums to see if practitioners/researchers can get larger image data. Following are the next steps that I can envision:

  1. Looking at other datasets, to extract the same features from them, to add to the dataset. 
  2. Downloading non-copyrighted images from Search Engines. Google's API allows only 64 images to be downloaded. I asked on their forum on how to filter images that are copyrighted.
I would like to create a framework that could create automated image datasets (non-copyrighted images) including translations and transformations. 


[1] Caffe Deep Learning Framework:
[2] Marko Ċ krjanec, Fruit Image Data set
[3] Convolution Neural Networks,

Tuesday, October 6, 2015

Running CUDA 7 on Ubuntu 14.04: blank screen after CUDA install: Solved

Update: CUDA 8 is awesome; and seems more stable.

Installation of CUDA on Ubuntu 14 has resulted in blank screen. After fixing those issues, the GUI login screen shows up, but login would not work. After multiple attempts to fix, either CUDA works or X works.

Trying to use Nouveau driver for GUI and Nvidia driver for CUDA, lead me to a blog [1]. It worked for me and thanks Chen.

Chen suggests to blacklist Nouveau (which CUDA installer does as well), remove and purge nvidia drivers, install CUDA. During this part, install Nvidia driver, but NOT the OpenGL driver.

And everything works. Thanks, Chen.

To fix Ubuntu's blank Screen

If Ubuntu boots to blank screen [2]:
  1. Goto command line: ctrl + alt + f1.
  2. Stop lightdm: sudo service lightdm stop
  3. Disable gpu-manager by backing up /etc/init/gpu-manger.conf and commenting its contents.
  4. Switch to prime mode by installing and using sudo prime-select nvidia
  5. Get the correct busid for nvidia: lspci | grep NVIDIA
  6. Update /etc/X11/xorg.conf with the correct busid. "PCI:01:00.0"
  7. Perform sudo chattr +i /etc/X11/xorg.conf
  8. Start lightdm: sudo service lightdm start

[1] Chen,