Category Archives: Programming languages

How To Update Node.js on MacOS: Hindsight on Old Mac

Updating packages and apps on MacOS is usually a trivial task. There are several avenues available, depending on the personal preference and degree of familiarity with various tools available on Mac. Now consider a case for updating Node.js (and subsequently npm) on MacOS. What are the options?

tl;dr Updating Node.js with lightweight package manager such as n is less error prone especially for older MacOS version

Let’s start by listing the options on our perusal.

Option 1: Download the installer from nodejs.org and install the binary

This option is ideal for the first installation. It is less ideal for update / version upgrade or if we want to maintain several nodejs versions on the machine. Continue reading

How to Open Multibyte CSV File Containing East Asian Characters (Chinese, Japanese, Korean) in Excel on MacOS

Excel on MacOS has its own quirk when dealing with CSV file. If you have a CSV file that is encoded with UTF-8 and contains entries in multibyte characters from East Asian languages such as Chinese, Japanese, Koreans, opening the file in Excel on MacOS may give you some surprise. Instead of showing the East Asian characters, Excel will display garbled characters.

Let us a run experiment to explain this case. We will use Node JS to create a CSV file, encode the file using UTF-8 and then try to open it using Excel on MacOS. Continue reading

How to Resolve The Error “Illegal instruction (core dumped)” when Running “import tensorflow” in a Python Program

There are several ways to install TensorFlow on Ubuntu. The easiest way is to install via pip. Unfortunately, this easy installation may result in a bumpy first time experience of running TensorFlow. Consider the following one line Python script:

$ python -c 'import tensorflow as tf;'

This should be where the excitement begins, the moment where conviction about the new era of AI-powered banalities starts to bloom. Yet, the reality can be unexpectedly different. Executing the command may immediately raise this very infamous error:

Illegal instruction (core dumped)

This means that TensorFlow has crashed even before it does anything. What a surprise!

The good thing is that we can run gdb to debug Python and start analyzing the call stack. But what’s even better is that we can save the brilliance for later. This error has been repeatedly reported and has conveniently sat on its fame for a while, as reflected on the issue page. Continue reading

ReactJS: Changing Default Port 3000 in create-react-app

Last update: January 15, 2022

If you are doing frontend development nowadays, you may have heard about ReactJS or may be actively using it in your projects. Introduced to the public five years ago, React has transformed into a library of choice for a lot of frontend developers that is easily certified by the enormous stars at its Github page (more than 100,000 stars). React was relicensed into MIT license almost a year ago, which only catapulted its popularity into a new high. The MIT license is a more commercial friendly license compared to the BSD + patents license that was previously used by React.

Creating a frontend project is easy with the help of scaffolding tools and boilerplates. Among the available choices is create-react-app, a React bootstrapping utility that takes care the laborious tasks of setting up a React project without much intervention about how the project should be structured. Given this nature, create-react-app is less assumed a boilerplate and more of a toolkit. Continue reading

How to Install Jupyter Notebook as Service for Tensor Flow and Deep Learning on Ubuntu 16.04

When developing a deep-learning system, especially during the modeling stage, a lot of trials and errors can be involved in evolving the codebase. The easy remedy to reduce errors will be by using a robust IDE that provides productivity-boosting features such as code completion, method definition, codestyle suggestion, advanced debugging, user-friendly UI, and so forth.

Another element for better development experience is interactivity. Instead of writing the whole source code and evaluate everything, it is arguably more productive to write the code in small steps, with one line as the smallest unit, and evaluate the code up to the last line written. This kind of mechanism is possible for scripting language where the codes are interpreted. Node JS for example has a feature named Read-Eval-Print Loop (REPL) that enables someone to write Javascript code with Node JS and has it evaluated on the go. Deep learning algorithms and systems are often developed in Python, another interpreted language. Similar initiative also exists for Python in the forms of interactive shell and “notebook”. A notebook is an interactive environment, normally with web GUI support, where someone can combine code execution, text, rich media, charting and other types of data visualization. A popular notebook for Python is Jupyter Notebook, which was formerly known as IPython Notebook.

In this article, we will go into more details about Jupyter Notebook installation and configuration on Ubuntu 16.04. However, it’s important to note that the configuration depends on some pre-requisites. This article is the continuation of the previous article about TensorFlow installation. Please make sure you have read the article to understand the pre-requisites, otherwise some steps explained in this article may not work. Continue reading