Interesting to watch this interview of 82 year old App Developer. She developed the app called Hinadan for people like her.

Here is her story.

Wakamiya asked software developers to step in to develop her app. Uninterested, they suggested she make a game herself. She took them up on the suggestion. Wakamiya soon bought programming books and learned Apple’s Swift programming language through lessons with a programmer, nearly 200 miles away from her home in Japan's Kanagawa Prefecture, via Facebook Messenger and Skype.

This wasn’t the first time that Wakamiya took on a challenge. She’s been dabbling in the tech field since the age of 60.

Upon retiring from a 43-year career as a bank clerk (she began at age 18), Wakamiya spent long hours caregiving for her then-90-year-old mother. Feeling isolated, and seeking connection with the outside world, Wakamiya bought her first computer, then moved on to a Microsoft PC, and later a Mac and iPhones. In between learning the piano, at age 75, Wakamiya eventually joined a computer club for seniors, Mellow Club, learning to create Excel art along the way. Then, this past year came Wakamiya’s focus on creating the game Hinadan.

The app, based on the annual Japanese doll festival of Hina Matsuri, invites players to arrange 12 ornamental dolls — representing the country’s emperor, family and guests — in a specific order. The game requires in-depth memorization of various arrangements, and has become especially popular with older women, who enjoy playing it with their grandchildren, Wakamiya said.

From - https://www.aarp.org/work/working-at-50-plus/info-2018/worlds-oldest-app-developer-fd.html

It is hard for me write a review for as a great a book as "Guns, Germs and Steel". I had not read anything like that before. It just opened me up to a whole new level of experience, and new set of expectations from books.

I think, I picked it up after reading Bill Gates review about this.

"Like a lot of people, I was blown away by Diamond's Guns, Germs and Steel. I had never read anything that explained so much about human history." - Bill Gates, On Guns, Germs and Steel

I made copious notes while reading this book, I wanted to preserve it for my future reference. I looked up many different incidents in Wikipedia while reading this book. Every moment I spent was totally worth it. It will give a reader a whole new understanding of the world. This book feels like a Magnum Opus, an experience provided to the reader.

The first captive thing presented to me in this book was The Battle of Cajamarca which lead to the fall of the Inca Empire in South American Continent in 1500s.

Here is some data on this Battle. The left hand side is Spanish, and the right side is Inca Empire.

Isn't that startling? What happened? The reader is taken through the reasons for such decisive victory.

Then it steps back and goes the reason for why some developments took place at the places it took place. This flow-chart from the book conveys the reason in a comprehensive way.

Then, a chapter on writing gives a whole history of human writing system. Which itself is fascinating, and the next chapter was titled "Necessity's Mother".

This is an interesting twist on the commonly known proverb, "Necessity is the mother of all inventions". It just asks, who was "Necessity's Mother". The answer is simple, it is the idle brain, curiosity. The chapter gives so many details on the inventions that really took the world. I briefly wrote about it in this post Edison and his phonograph when I was reading that chapter.

Then it deals with the idea of how the concept society and a religion must have formed. In the final chapters, it goes into the fascinating story of China and Africa.

Here is one thing about China that amazed me.

Think about it, China sent huge ships with lots of people to expeditions way before Columbus set his foot on America!

And the chapter on Africa, tells about the diversity of Africa, mentions about 1500 languages that originated in Africa. And shares something that is very interesting.

This just says two of modern religions of the world originated by the speakers of an African language.

This book is an answer from Jared Diamond to his friend from Papau New Guinea, on why westerners were more advanced than his tribe. It does a great job of giving that answer to Mr. Yali and rest of us.

Edison had invented phonograph, a precursor to modern day music player and phone, but he not could get the proper utility value of his invention immediately. I came across this paragraph in a book called, "Guns, Germs and Steel" and felt compelled to note it down.

The Manga Guide to Linear Algebra by Shin Takahashi
My rating: 4 of 5 stars

Manga Guide to Linear Algebra is a manga comic that teaches linear algebra concept. When I stumbled upon the terms Eigenvalues and Eigenvectors, I found those were greek to me, and I had no intuitive understanding of those terms. I decided to spend 4-hours to read about the basics of linear algebra from this book.

The book starts with the concept of sets, functions, and relations. Then introduces matrices, and then vectors. It gives a gentle introduction to various matrix operations. Gives visual clue on vector representations. Introduces the concept of linear dependence and linear independence in vectors.

Shows the examples of linear transformations which are practical applications of linear algebra and finally goes to introduce eigenvalues and eigenvectors. Finally, for Eigenvalues and Eigenvectors, these are the examples that are shown.

This is a example of 2x2 matrix for illustrating Eigenvectors given in the book.

c_1[3, 1] + c_2[1, 2] [[8 -3]     -> c1[21, 7] + c_2[2, 4]
                       [2  1]]

c_1[3, 1] + c_2[1, 2] -> f[[8 -3]    -> c_1[7 [3, 1]] + c_2[2 [1, 2]]
                           [2  1]]

The image of the expression using the linear transformation, expressed using the same original vectors, but with coefficients, 7 and 2 now. Then gives the example of 3 dimentional vector, and finally explains the the concept of Eigenvalue and Eigenvectors.

In the above example, 7 and 2 are eigenvalues, and (3, 1) and (1, 2) are the eigenvectors associated with those eigen values.

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The word eigen seems to have come from german which means proper or characteristic. It seems that we express the original expression with the linear transformation properly using some values and vectors.

Image and Video Processing - From Mars to Hollywood with a Stop at the Hospital is the course offered by Guillermo Sapiro at Coursera. After a long time, I voluntarily took a course and finished it. I didn't pay for the course and so, I won't get a certificate. But I have this, and the course completion recorded in my accomplishments in coursera.

It was wonderful course, I learnt about digital signal processing, and image transformations.

I read this paper titled Shelling Out. The Origins of Money by Nick Szabo It starts with the origin of money in the european colony of the americas, how and why a mass scale currency was introduced by colonists upon the native americans.

Based on this anecdote, it discusses some of the important properties of money.

It defines the role of money to a basic human need for co-operation. Money, it says is delayed exchange of altruism on part by humans. And money sould have properties like non-stealable, non-reproducible in order to be valuable. The human society devised multiple tools for this kind. When the problem was met with scale, they invented a "fiat currency", started in China, was way to scale currency, and keep a ledger for supply and demand. The coin system that was first invented in Lydia is the same coin system that we use today, and the fiat currency is still in use. Except now that we have the technology to scale currency without trusting or depending on a government to maintain a ledger.

I recollected this favorite poem of my mine from school days. I first read it in a Sportstar magazine and I don't know the author of this poem.

When trying to understand the concept of radians, I came across the inventor of the concept Roger Coats His name is not familiar to many. I understood, he is known for working closely with Isaac Newton by proofreading the second edition of his famous book, the Principia, before publication.

Cotes died from a violent fever in Cambridge in 1716 at the early age of 33. Isaac Newton remarked, "If he had lived we would have known something."

Beyond the Door by Philip K. Dick
My rating: 2 of 5 stars

A simple, imaginative book. Couldn't think about the plot. If it were a different author, this book or story would have been long dead.

Apache Mesos Essentials by Dharmesh Kakadia
My rating: 3 of 5 stars

A simple overview of Mesos. It enlists the commands and scripts that will be useful to operate a Mesos cluster. Gives an overview of Hadoop and Spark data frameworks and how they can launched on Mesos. It is aimed at operators and system engineers trying to operate Mesos.