April 2025
Intermediate to advanced
578 pages
13h 35m
Portuguese (Portugal, Brazil)
Content preview from R for Data Science, 2ª Edição
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Capítulo 26. Iteração
Este trabalho foi traduzido com recurso a IA. Agradecemos o teu feedback e comentários: translation-feedback@oreilly.com
Introdução
Neste capítulo, aprenderás ferramentas para iteração, executando repetidamente a mesma ação em diferentes objectos. A iteração em R geralmente tende a parecer bastante diferente de outras linguagens de programação, porque grande parte dela é implícita e a obtemos de graça. Por exemplo, se quiseres duplicar um vetor numérico x em R, podes simplesmente escrever 2 * x. Na maioria das outras linguagens, terias de duplicar explicitamente cada elemento de x utilizando algum tipo de ciclo for.
Este livro já te deu um pequeno mas poderoso número de ferramentas que executam a mesma ação para várias "coisas":
-
facet_wrap()efacet_grid()desenha um gráfico para cada subconjunto. -
group_by()maissummarize()calcula um resumo estatístico para cada subconjunto. -
unnest_wider()eunnest_longer()cria novas linhas e colunas para cada elemento de uma coluna de lista.
Agora é hora de aprender algumas ferramentas mais gerais, muitas vezes chamadas de ferramentas de programação funcional porque são construídas em torno de funções que recebem outras funções como entradas. Aprender programação funcional pode facilmente desviar-se para o abstrato, mas neste capítulo vamos manter as coisas concretas, concentrando-nos em três tarefas comuns: modificar várias colunas, ler vários ficheiros e guardar vários objectos.
Pré-requisitos
Neste capítulo, vamos ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.