Tag: column

Feed: R-bloggers. Author: mrtnj. Since version 1.0.0, released in September, the tidyr package has a new replacement for the gather/spread pair of functions, called pivot_longer/pivot_wider. (See the blog post about the release. It can do a lot of cool things.) Just what we needed, another pair of names for melt/cast, right? Yes, I feel like this might just be what we need! My journey started with reshape2, and after a bit of confusion, I internalised the logic of melt/cast. Look at this beauty: library(reshape2) fake_data This turns a data frame that looks like this … id variable1 variable2 1 1 ... Read More

Feed: R-bloggers. Author: R Views. [This article was first published on R Views, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. In a previous post, we explored IPOs and IPO returns by sector and year since 2004. Today, let’s investigate how portfolios formed with those IPOs have performed. We will need to grab the price histories of the tickers, then form portfolios, then calculate their performance, and then rank those performances in some ... Read More

Feed: R-bloggers. Author: R | datawookie. [This article was first published on R | datawookie, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here) Want to share your content on R-bloggers? click here if you have a blog, or here if you don't. The Durban EDGE (Economic Development and Growth in eThekwini) DataQuest was held at UKZN (Westville Campus) on 13 November 2019. Participants were tasked with creating something interesting and useful with the civic data on the new Durban EDGE Open Data Portal developed by Open Data Durban. These datasets were available: ... Read More

Feed: Planet PostgreSQL. OSM to PostGIS – The BasicsEver wondered how to import OSM (OpenStreetMap) data into PostGIS [1] for the purpose of visualization and further analytics? Here are the basic steps to do so.There are a bunch of tools on the market— osm2pgsql; imposm; ogr2org; just to mention some of those. In this article I will focus on osm2pgsql [2] .Let’s start with the software prerequisites. PostGIS comes as a PostgreSQL database extension, which must be installed in addition to the core database. Up till now, the latest PostGIS version is 3, which was released some days ago. For ... Read More

Feed: R-bloggers. Author: Rahim Rasool. Logistic regression is one of the statistical techniques in machine learning used to form prediction models. It is one of the most popular classification algorithms mostly used for binary classification problems (problems with two class values, however, some variants may deal with multiple classes as well). It’s used for various research and industrial problems. Therefore, it is essential to have a good grasp on logistic regression algorithm. This tutorial is a sneak peek from many of Data Science Dojo’s hands-on exercises from their 5-day data science bootcamp, you will learn how logistic regression fits a ... Read More

Feed: Planet PostgreSQL. Postgres has extensions, and that’s awesome! Of course as the author of CREATE EXTENSION I’m a little biased… just remember that the ability to extend Postgres is way more than just this command. The whole database system has been design from the ground up to allow for extensibility. Parts of the design is to be found in the way you can register new objects at runtime: functions of course, and also data types, operators, index support structures such as operator classes and families, even index access methods! Today’s article shows a query that you can use to ... Read More

Feed: Planet MySQL; Author: Mark Callaghan; How do you use an LSM for analytics? I haven't thought much about it because my focus has been small data -- web-scale OLTP since 2006. It is a great question given that other RocksDB users (Yugabyte, TiDB, Rockset, CockroachDB) support analytics.This post isn't a list of everything that is needed for an analytics engine. That has been described elsewhere. It is a description of problems that must be solved when trying to use well-known techniques with an LSM. I explain the LSM challenges for a vectorized query engine, columnar storage, analytics indexes and ... Read More

Feed: Microsoft Power BI Blog | Microsoft Power BI. Author: . The ribbon in Power BI Desktop has an updated and modern experience. When you turn on the “Updated ribbon” preview feature, you will see a ribbon that looks more like the ribbon in Office products. In the updated ribbon, you have access to all the existing features that you know and love, and over time, more features will be added to the ribbon. If you have feedback about the updated ribbon, we’d love to hear from you! The Journey When we started the journey of redesigning the ribbon, some ... Read More

Feed: Microsoft Power BI Blog | Microsoft Power BI. Author: . The November update has major updates in several areas of Power BI Desktop. There’s a new, modern ribbon that aligns Power BI Desktop with Office and adds more functionality. We’re also adding a new visual, the decomposition tree, which is one of the most requested ideas on ideas.powerbi.com. AI functions integrated into Power Query allows you to take your data transformations to the next level, and of course we have incremental improvements across the entire product. Here’s the complete list of November updates: Other Reporting Analytics Visualizations Data connectivity ... Read More

Feed: Clustrix Blog. Author: Anders Karlsson. There are several ways to load data into MariaDB Platform, and some are better than others. The two basic ways are either to use LOAD DATA INFILE / LOAD DATA LOCAL INFILE, which is very fast, in particular the non-LOCAL one and then we have the plain INSERT statement. When using an INSERT statement you may pass an array to MariaDB Server, like thisINSERT (column1,column2) VALUES(, ),(, ) Nothing special with that, but what we will cover in this blog is another way of doing INSERTs using arrays, one which uses the MariaDB API ... Read More