Читать книгу The Big R-Book - Philippe J. S. De Brouwer - Страница 184

1 1 There are different package management systems for different flavours of Linux and discussing them all is not only beyond the scope of this book, but not really necessary.We assume that if you use Genttoo, that you will know what to do or where to choose.

2 a This behaviour is caused by the dispatcher-function implementation of an object-oriented programming model. To understand how this works and what it means, we refer to Section 6.2 “S3 Objects” on page 122.

3 2 The character type in R is what in most other languages would be called a “string.” In other words, that is text that – generally – will not allow much arithmetic.

4 a See Chapter 7 “Tidy R with the Tidyverse” on page 161 and note that tibbles (the data-frame alternative in the tidyverse) do not coerce text to factors.

5 3 If your programming experience is limited, this might seem a little confusing. It is best to accept this and read further. Then, after reading Section 5.1 “Environments in R” on page 110 have another look at this section.

6 4 A direct link to this file (in zip-format) is here: http://www.ecb.europa.eu/stats/eurofxref/eurofxref-hist.zip?c6f8f9a0a5f970e31538be5271051b3c.

7 5 With R it is also possible to read files directly from the Internet by supplying the URL in to the function read.csv().