April 2025
Intermediate to advanced
582 pages
13h 33m
Portuguese (Portugal, Brazil)
Content preview from Python para Análise de Dados, 3ª EdiçãoBecome 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 8. Organizar dados: Unir, combinar e remodelar
Este trabalho foi traduzido com recurso a IA. Agradecemos o teu feedback e comentários: translation-feedback@oreilly.com
Em muitas aplicações, os dados podem estar espalhados por vários ficheiros ou bases de dados, ou estar organizados de uma forma que não é conveniente para analisar. Este capítulo concentra-se em ferramentas que ajudam a combinar, unir e reorganizar dados.
Primeiro, introduzo o conceito de indexação hierárquica no pandas, que é utilizado extensivamente em algumas destas operações. Em seguida, exploro as manipulações de dados específicas. Podes ver várias utilizações aplicadas destas ferramentas no Capítulo 13.
8.1 Indexação hierárquica
A indexação hierárquica é uma importante caraterística do pandas que lhe permite ter vários (dois ou mais) níveis de índice num eixo. Outra forma de pensar sobre isso é que fornece uma maneira de trabalhar com dados de maior dimensão em uma forma de menor dimensão. Vamos começar com um exemplo simples: cria uma Série com uma lista de listas (ou matrizes) como índice:
In[11]:data=pd.Series(np.random.uniform(size=9),....:index=[["a","a","a","b","b","c","c","d","d"],....:[1,2,3,1,3,1,2,2,3]])In[12]:dataOut[12]:a10.92961620.31637630.183919b10.20456030.567725c10.59554520.964515d20.65317730.748907dtype:float64
O que estás a ver é uma vista embelezada de uma Série com um MultiIndex como índice. Os "intervalos" na apresentação do índice ...
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.