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Big Oh notation and Algorithmic Complexity analysis

Introduction When executing a particular task using algorithms, one common thing that hits every problem solver brain is the efficient and fast algorithm to solve that problem. But, what do exactly fast and efficient means? Is it the measure of real processing time? No, it's not the measure of real time like second and minutes because the old computer with Pentium processor may take a long time to process the same algorithm than the new Intel i3 processor, or, A bad algorithm written in Assembly may execute faster than a good algorithm written in python. So, run time of program can't be considered to measure algorithmic efficiency. 
Hence, to measure the algorithmic efficiency, the concept of Asymptotic Complexity of a program and a notation for describing this called Big Oh  was introduced. Big Oh is the worst case, Big Omega and Big Theta are best and average case notations. Worst case means we are mostly unlucky for that problem domain , i.e precondition of task do not fav…

sed(stream editor) command in Linux/Unix

Introduction to stream editor A stream editor is a tool that transforms text, edit a file and replaces file content with the manipulation using the regular expression. Why I used Stream Editor? I find this tool handy and more useful when I have to change a word of a file line by line. I faced this issue while updating my Debian operating system from Jessie "Debian 8" to stretch "Debian 9" for that, I have to update my /etc/apt/sources.list file, in which I have to change the each "Jessie" word in that file  to "stretch" So, I use this command
sudo sed -i 's/jessie/stretch/g' /etc/apt/sources.list
Here the "s" specifies the substitution. The "/" are delimiters. "jessie" is the search pattern and "stretch" is the replacement pattern.  for more refer to sed manual page here or prefer manual page in your machine for sed commands.

Error during activeadmin gem installation on Rails 5.0 app

Troubleshooting Error with rails activeadmin gem Installation.
Ever faced this error below with gem activeadmin installation in rails 5
Your bundle requires gems that depend on each other, creatingan infinite loop. Please remove gem 'meta_search' and tryagain.

Include this line in your Gemfile
gem 'activeadmin', github: 'activeadmin' update your bundle doing this.
bundle update This error will appear in your console






Fetching https://github.com/activeadmin/activeadmin.gitFetching gem metadata from https://rubygems.org/.........Fetching version metadata from https://rubygems.org/..Fetching dependency metadata from https://rubygems.org/.Resolving dependencies...Bundler could not find compatible versions for gem"actionpack": In Gemfile: activeadmin was resolved to 1.0.0.pre4, which depends onformtastic (~> 3.1) was resolved to 3.1.4, whichdepends on actionpack (>= 3.2.13) activeadmin was resolved to 1.0.0.pre4, which depends oninherited_…

All you need to know about Quick Sort Algorithm.

Introduction to Quick Sort Algorithm. A sorting algorithm basically sorts the data structure like array or list in certain order. The order either may be the numerical order or alphabetical order. A Quick-Sort Algorithm is one of the fastest sorting algorithms, which sorts the array based on partitioning the array by choosing an element of the same array as a pivot. All element greater than the pivot are moved to the right direction and all element smaller than the pivot are moved to left.
The basic idea of this algorithm is to select a pivot element in an array and to put the pivot element in its right place and move all smaller entries than pivot of the array to left, and greater entries than pivot to right of the array.  Now the array is divided into two part one part of greater entries than the pivot and another part of the smaller entries than the current pivot element. Now the two-part are recursively applied quicksort to left part and to the right part. Recursion basically ref…

Going Through MNIST(Mixed National Institute of Standards and Technology) Datasets in TensorFlow

MNIST Talking About MNIST(Mixed National Institute of Standards and Technology), It is the larger database of the handwritten digit which is used to train and test various Machine learning and Image processing task. [MNIST Wikipedia entry]
As a beginner to Machine learning and equally beginner to TensorFlow, I have decided to go through the first tutorial entitledMNIST For ML Beginners (Mixed National Institute of Standards and Technology)

[In Tensorflow tutorials, make sure to use the your version of mnist_softmax.py by selecting version in branch section, Do not use master branch because the tutorial will be of different tensorflow version ] for tensorflow 0.11 mnist_softmax.py file]

I started my development environment on Pycharm IDE with interpreter location at virtual environment tensorflow which I created previously during Installation of TensorFlow.
 Going through TutorialsThe data hosted on yann.lecun.com is automatically downloaded and read. This is all that tutorials say. from …

Getting Started With Tensorflow

TensorFlow Introduction It is an open source library for machine learning. It was developed at Google by Google brain team. For more info regarding Tensorflow check the Wikipedia entry.

Getting Started with Installation Referring to GitHub link and choosing the virtual environment Installation Procedure. Following this link here for installation procedure of Tensorflow library  CPU version. We can choose any version listed along with CPU/GPU version.
After activating the python virtual environment as listed on installation manual console of our environment will be changed like this as in the picture below.
After this steps below,
export TF_BINARY_URL=https://storage.googleapis.com/tensorflow/linux/cpu/tensorflow-0.11.0-cp27-none-linux_x86_64.whl pip install --upgrade $TF_BINARY_URL Faced a problem during installation with this message in console.
tensorflow-0.11.0-cp27-none-linux_x86_64.whl is not a supported wheel on this platform.


Troubleshooting installation problem Since this whee…