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Romesh Maling Perera

Finding a solution for hard questions was one of my hobbies from my childhood. You will find me on almost all problem solving web sites, like top coder, project eular, Hacker Rank, etc. My hobby leads my way towards being an engineer. I play lot of strategy games like Age of Empires, League of Legends, Command and conquer, etc. Team play and good communication can change a game, If you agree with me add me as a League of Legends friend. Having my school education from Maris Stella College, I was selected to the University of Moratuwa having the best advance level results (in mathematics section) in my school. I have the dream of being a part of the biggest changes in the world. I was able to be batch 5th in first year field-selection examination in University of Moratuwa. My dream had its hand on my selection of Computer Science and Engineering Field after the field selection exam. I completed my Industrial training in WSO2 Lanka (pvt) Ltd. Currently I am working in Leapset (pvt) Ltd Specialties: Software Engineering, Marketing, Technical Writing, Presentation Skills, Music, Karate, Real time strategy games.

Finding a solution for hard questions was one of my hobbies from my childhood. You will find me on almost all problem solving web sites, like top coder, project eular, Hacker Rank, etc. My hobby leads my way towards being an engineer. I play lot of strategy games like Age of Empires, League of Legends, Command and conquer, etc. Team play and good communication can change a game, If you agree with me add me as a League of Legends friend.

Having my school education from Maris Stella College, I was selected to the University of Moratuwa having the best advance level results (in mathematics section) in my school. I have the dream of being a part of the biggest changes in the world. I was able to be batch 5th in first year field-selection examination in University of Moratuwa. My dream had its hand on my selection of Computer Science and Engineering Field after the field selection exam.

I completed my Industrial training in WSO2 Lanka (pvt) Ltd. Currently I am working in Leapset (pvt) Ltd

Specialties: Software Engineering, Marketing, Technical Writing, Presentation Skills, Music, Karate, Real time strategy games.

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Jaro–Winkler Similarity – How to correctly count the number of transpositions

Jaro–Winkler Similarity is a widely used similarity measure for checking the similarity between two strings. Being a similarity measure (not a distance measure), a higher value means more similar strings. You can read on basics and how it works on Wikipedia. It’s available in many places and I’m not going… Read More »Jaro–Winkler Similarity – How to correctly count the number of transpositions

Sri Lanka Holidays Calendar 2016 for Outlook & Google

Sri Lanka Holidays Calendar 2020 for office365, Google etc. in ics format

Edit: If you are looking for 2021 calendar, visit https://www.malinga.me/sri-lanka-holidays-calendar-2021-for-office365-google-etc-in-ics-format/ Honouring everyone’s request I added the Sri Lankan Holiday calendar for 2020. This will allow you to add the Sri Lanka Holidays Calendar 2020 to your digital calendar (Most of the online digital calendars that we use these days don’t… Read More »Sri Lanka Holidays Calendar 2020 for office365, Google etc. in ics format

What-if Analysis with SQL server (Hypothetical Indexes) – Using python

What-if Analysis with SQL server (Hypothetical Indexes) – Using python

If you are a Database administrator or a developer working with a transaction database, you might have come across this problem “Is it worthy to build that index?” Exact answer for that question is only known once you build it. However, luckily SQL server provides you with functionality to check… Read More »What-if Analysis with SQL server (Hypothetical Indexes) – Using python

Sri Lanka Holidays Calendar 2016 for Outlook & Google

Sri Lanka Holidays Calendar 2019 for office365, Google etc. in ics format

Honouring everyone’s request I added the Sri Lankan Holiday calendar for 2019. This will allow you to add the Sri Lanka Holidays Calendar 2019 to your digital calendar (Most of the online digital calendars that we use these days don’t have inbuilt option to add the holiday calendar for Sri… Read More »Sri Lanka Holidays Calendar 2019 for office365, Google etc. in ics format

Sri Lanka Holidays Calendar 2016 for Outlook & Google

Sri Lanka Holidays Calendar 2018 for office365, Google etc. in ics format

As Everyone requested I added the Sri Lankan Holiday calendar for 2018 . This will allow you to add the Sri Lanka Holidays Calendar 2018 to your digital calendar (Most of the online digital calendars that we use these days don’t have in built option to add the holiday calendar… Read More »Sri Lanka Holidays Calendar 2018 for office365, Google etc. in ics format

Negombo Toastmasters Club 8th Installation Ceremony for year 2017/2018

Negombo Toastmasters held its eighth Executive Committee Installation Ceremony for 2017/2018 on 12 August 2017 at Paradise Beach Hotel, Negombo. The Chief Guest was DTM Arjuna ⁠⁠⁠Jayadarshana and the Guest of Honor was TM Sudath Fernando who is a charter member of Negombo Toastmasters Club. Area Director for District 89 Area H4 Sudath Ranaweera was also present at the occasion. Another two of our charter members TM Mohammed Marzook, Division Director TM Anura Perera also joined us on this important day.

Negombo Toastmasters Club 8th Installation Ceremony for year 2017/2018

The following officers for 2017/2018 were installed at the ceremony.

  • President – TM Tony Ukwattage
  • Vice President/Education – TM Bavanitha Rajagugan
  • Vice President/Membership – TM Gihan Wijayatilake
  • Vice President/Public Relations – TM Romesh Malinga Perera
  • Secretary – TM Tissera Maduranga
  • Treasurer – TM Buddika Liyanage
  • Sergeant-at-Arms – TM Shehan Gunasinghe

Read More »Negombo Toastmasters Club 8th Installation Ceremony for year 2017/2018

Performance evaluation between different Druid roll-up levels

Introduction

In most datasets with a large number of events, going through individual events is less important. Most of the data use cases are around the summarized data. Druid summarizes this raw data at ingestion time using a process refer to as “roll-up”. Roll-up is the highest granularity of the data and will be able to query only up to the roll-up granularity. However, there are some scenarios where it’s important to have more granular data. However keeping more granular data comes at a cost. We did a small experiment to identify how different roll-up levels affect performance.

Rolling up data can dramatically reduce the size of data that needs to be stored (up to a factor of 100). Druid will roll up data as it is ingested to minimize the amount of raw data that needs to be stored. This storage reduction does come at a cost; as we roll up data, we lose the ability to query individual events. Phrased another way, the rollup granularity is the minimum granularity you will be able to explore data at and events are floored to this granularity. Hence, Druid ingestion specs define this granularity as the queryGranularity of the data. The lowest supported queryGranularity is millisecond. -http://druid.io

Dataset and Setup

We choose a CSV data set with millions (150M+) of records which contain sales data spanning across 2 years. CSV file was around 6 GB in physical size. This is a narrow data set with 3 dimensions and 2 metrics. We had 2 servers where all the components are deployed.

m4 large – Coordinator, Brokers, Overload nodes
r3 large – Middle managers and Historical nodes

Read More »Performance evaluation between different Druid roll-up levels

Suzuki WagonR Hybrid (Stingray) – Fuse design (Identifying and changing the blown fuse)

Suzuki WagonR Hybrid (Stingray) – Fuse design (Identifying and changing the blown fuse)

Introduction

We all come across some situations where some electronic features are not working suddenly. Most of the time it relates to a blown fuse. In this article, we talk about how to identify and replace a blown fuse. When doing this, it is always recommended to have a good idea about what functionalities relate to each fuse. So mainly in this article, we will talk about Suzuki WagonR Hybrid fuse design.

Where can we find the fuses in Suzuki WagonR Hybrid?

Mainly fuses found in five places. However, we are talking about three out five places where you will find fuses related to electronic accessories.

Under the Steering Wheel

Suzuki WagonR Hybrid (Stingray) – Fuse design - Under the Steering wheel Suzuki WagonR Hybrid (Stingray) – Fuse design - Under the Steering wheel

Fuse design

Suzuki WagonR Hybrid (Stingray) – Fuse design - Under the Steering wheel

Read More »Suzuki WagonR Hybrid (Stingray) – Fuse design (Identifying and changing the blown fuse)

Sri Lanka Holidays Calendar 2017 for office365, Google etc. in ics format

Sri Lanka Holidays Calendar 2016 for Outlook & Google As Everyone requested I added the Sri Lankan Holiday calendar for 2017 . Seems like this year is a good year in the terms of holidays (only till May 🙁 ).  This will allow you to add the Sri Lanka Holidays Calendar 2017 to your digital calendar (Most of the online digital calendars that we use these days don’t have in built option to add the holiday calendar for Sri Lanka). Download ICS format 2017 Sri Lankan holiday calendar .

Adding to office365

  1. Add calendar
  2. From file (don’t go to holiday calendar, Sri Lanka is not available there)
  3. Select file to upload and a calendar that holidays will be added (Create a separate new calendar is recommended. Use RED color)
  4. Save

Read More »Sri Lanka Holidays Calendar 2017 for office365, Google etc. in ics format