Back in school, you must remember studying differential and integral calculus. Now what on earth is lambda calculus? Well, lambda calculus is basically a simple notation for functions and applications in mathematics and computer science. It has a significant impact in the field of programming language theory. It forms the basis for all the modern functional programming languages like Haskell, Scala, Erlang, etc. The main idea here is to apply a function to an argument and forming functions by abstraction. The good thing about lambda calculus is that the syntax is quite sparse, which makes it an elegant notation for representing functions. Here, we get a well-formed theory of functions as rules of computation. We will discuss this further soon. Even though the syntax of lambda calculus is sparse, it is really flexible and expressive. This feature makes is particularly useful in the field of mathematical logic. So what exactly is lambda calculus? How do we understand it? Continue reading “A Beginner’s Look At Lambda Calculus”
Autoencoders In Machine Learning
When we talk about deep neural networks, we tend to focus on feature learning. Traditionally, in the field of machine learning, people use hand-crafted features. What this means is that we look at the data and build a feature vector which we think would be good and discriminative. Once we have that, we train a model to learn from it. But one of the biggest problems with this approach is that we don’t really know if it’s the best possible representation of the data. Ideally, we would want the machine to learn the features by itself, and then use it to build the machine learning model. Autoencoder is one such neural network which aims to learn how to build optimal feature vector for the given data. So how exactly does it work? How is it used in practice? Continue reading “Autoencoders In Machine Learning”
Why Do We Need Two-Factor Authentication?
In the last couple of years, we have encountered quite a few security breaches. A lot of internet companies are being targeted with these kinds of attacks. One of the most common forms of online transactions is that you have an account that’s protected with a password. So whenever you want to access your account, you just enter your username along with the password. But the problem is that this is breakable! As in, people can technically break into these accounts. So people started thinking about different ways in which this could be prevented. Of course, choosing better passwords would help, but we need to way to fundamentally improve the security. How exactly do we do it? Do we just choose bigger and better passwords or is there something new we can do? Continue reading “Why Do We Need Two-Factor Authentication?”
Static vs Dynamic Typing
If you are a programmer, you must have heard the terms “static typing” and “dynamic typing” being thrown around a lot. When we talk about programming languages, this is an important feature that tends to significantly affect the programs written in that language. In the spirit of simplicity, I will try to keep this post as code-free as possible. Actually, you don’t have to know any programming language in particular to understand this concept. If you are doing a hobby project or doing something simple, this will not come into picture and it will not affect your code as such. As you build bigger systems, static and dynamic typing will become a big concern. If you are not fully aware of the limitations of a given programming language, you will end up spending a lot of time in code maintenance. So it’s always good to know some of these things. Alright, so what exactly is it about? Does it really matter that much? Continue reading “Static vs Dynamic Typing”
Exploring The Hidden C++ Features
People have been using C++ for a long time now and most of us think that we are pretty well versed with it. Interestingly enough, as we spend more time with something, we keep discovering more things about it. I love it when the thing you have been using for so long turns out to have powerful hidden features. I encounter a lot of C++ in my day-to-day life and so I end up spending a lot of time with it. Over time, as I delved deeper into C++, I came across some abstruse features, some of which really surprised me! So I thought I should write about them. Let’s see what they are. Continue reading “Exploring The Hidden C++ Features”
Understanding Python “Property”
I was tinkering with Python the other day when I encountered the “property” keyword. I had seen it many times before and I sort of knew what it does, but I never really had a chance to dig deep into it. As it turns out, “property” in Python is very useful when you are designing large systems. People who come from the world of object oriented programming will appreciate it right away. It’s a nifty little concept which makes the life of a programmer much simpler. So what is it all about? Before we jump directly into what it is, let’s get some perspective as to why we would need it in the first place. Continue reading “Understanding Python “Property””
What’s The Importance Of Hyperparameters In Machine Learning?
Machine learning is becoming increasingly relevant in all walks of science and technology. In fact, it’s an integral part of many fields like computer vision, natural language processing, robotics, e-commerce, spam filtering, and so on. The list is potential applications is pretty huge! People working on machine learning tend to build models based on training data, in the hope that those models will perform well on unseen data. As we all know, every model has some parameters associated with it. We want our machine learning models to estimate these parameters from the training data. But as it turns out, there are a few parameters that cannot be estimated using this procedure. These parameters tend have a significant impact on the performance of your model. Now why is that? Where do these parameters come from? How do we deal with this? Continue reading “What’s The Importance Of Hyperparameters In Machine Learning?”
Is There A Problem With ‘git pull’?
This post is specifically about a particular command in git. If you are new to git or don’t know what git is, then this post may not make much sense to you. Now that the statutory warning is out of the way, let’s carry on. This is actually a continuation of my previous blog post. The command we are going to talk about is ‘git pull’. This command that brings the changes in the remote repository to where you keep your own code. This is done by bringing the local copy of the remote repository up to date first, and then merging the changes into your own code repository and possibly your working copy. A lot of people use it very frequently without thinking about the possible side effects. When I first started out with git, I didn’t really concern myself with these side effects either. But programming purists would say that ‘git pull’ is risky and should be used with caution. Why is that? Continue reading “Is There A Problem With ‘git pull’?”
git fetch vs git pull
Git is one of the most popular version control systems available out there. If you are a programmer, you must have used it one time or the other. This post deals with a couple of specific commands. So if you are new to git, this post may not make much sense to you. Git offers a variety of powerful commands to control the source code and collaborate with your peers on software projects.Every time I have to tinker with git, I tend to learn something new. In this post, we will discuss the difference between ‘git fetch’ and ‘git pull’. Continue reading “git fetch vs git pull”
Image Classification Using Fisher Vectors
This is a continuation of my previous blog post on image classification and the bag of words (BoW) model. If you already know how BoW works, then you will feel right at home. If you need a refresher, you can read the blog post here. In our previous post, we discussed how BoW works, and how we construct the codebook. An interesting thing to note is that we don’t consider how things are ordered as such. A given image is treated as a combination of codewords regardless of where they are located with respect to each other. If we want to improve the performance of BoW, we can definitely increase the size of the vocabulary. If we have more codewords, we can describe a given image better. But what if we don’t want to do that? Is there a more efficient method that can be used? Continue reading “Image Classification Using Fisher Vectors”
Perpetual Enigma 