Chapter 3 Getting started with BrailleR
The BrailleR package has been created for the benefit of blind people wishing to get more out of R than it already offers — which is actually quite a lot!
3.1 Accessibility of statistical software
A description of what makes statistical software accessible to the blind was given by (Godfrey and Loots 2014). Many of the problems blind people face are a consequence of the failure of the specialist screen reading software we use to interact with graphical user interfaces. Many software applications are making use of graphics when once the information would be presented in text form with an accompanying graph. — SPSS (SPSS Inc. 2012) is an example of this, and to a lesser extent so is the standard edition of Minitab (Minitab Inc. 2012). The output from Minitab Express (Minitab Inc. 2014) is a prime example of the worst possible presentation of information that was originally text; this product generates graphics that include text which is not readable by a blind person for all of its statistical output. The speech output software used by blind people can only interpret information that is text. As a guide, if the individual text in a window cannot be highlighted using the keyboard and not the mouse, then it is likely that this text will not be read for the blind user.
It is true that some add-on packages for R also generate unreadable output, but as illustrated below, this is less of an issue than for software like SPSS or Minitab. (Godfrey and Loots 2014) gave more detailed scrutiny of R, SAS (SAS Institute Inc. 2010) , SPSS, and Minitab. Of these four applications, R and SAS were clearly superior to SPSS and the standard edition of Minitab.
Some software applications have retained their historical links to the days when graphs and tables were rendered in well controlled monospace fonts — Minitab for example. In such applications the user may still be able to produce an ASCII graphic instead of the more commonly used high resolution graphs expected of today’s software (and user). In contrast, SAS and SPSS can use HTML to present information in well-formatted tables. These output windows are preferred by blind users over the graph window displays but sometimes the amount of information is not easily understood. Presentation of output is often read by eye in a vertical direction, while speech output software will read line by line. Take for example, a multiple regression where the sighted reader may scan down the list of p values in the right hand column; the same information being read aloud in line by line style could prove quite difficult to interpret. Blind users can use combinations of keys to move around HTML tables to speed up this process and avoid reading the intervening columns of output. While SPSS and SAS can deliver formatted HTML as a matter of course, R users must resort to the add-on packages, many of which are available on CRAN.
3.2 Accessibility of R
(Godfrey 2013b) documented the ability to use R almost immediately after installation; only one minor change is recommended and can be achieved in less than a minute even when explained via email or a telephone call. For users of the Windows operating system, up until Windows XP, I always recommended running R in a terminal window instead of the GUI; the shortcut placed on the Windows desktop would then need to be pointed to Rterm.exe instead of Rgui.exe.
Macintosh and Linux users are operational with no special actions required.
Users of Windows Vista or Windows 7 did have an additional challenge of what appeared to be the screen locking up, or more exactly, the screen reader software “losing focus” in the R terminal window. The solution for this problem, as documented in (Godfrey and Erhardt 2014), was to hit the Alt key.
Blind users now need to compare the combinations of screen reader and the terminal versus the GUI.
The decision should be made by the individual user after some experimentation; their decision may depend on the skill level they have with their prefered screen reader and should be revisited at a later date.
Blind students attending the R workshop at the 2011 Summer University, held in the Czech Republic, were able to set up R for use in a classroom setting on their own machines. This included a variety of operating systems and adaptive technology (hardware and software for blind people). Similar events were held in 2013 and 2014 but most attendees used computers supplied by the host organizing committees. Many attendees have made contact when issues have arisen, but none of the issues relate to the installation of R or its interactions with the particular hardware or software being used. I am confident that anyone intending to undertake use of any statistical software will be able to get R working with their screen reader.
3.3 Installing the BrailleR package
To use the functionality of the BrailleR package you need to have it installed. The package has several dependencies so installation from the CRAN repository is recommended. This would be done by issuing the following two commands in an R session:
chooseCRANmirror(ind=1)
install.packages("BrailleR")Note that the first and last letters of BrailleR are capitalised. This is important in R, but is also useful for screen reading software which will then give audibly different feedback, as compared to what a screen reader user hears from the lower case text “brailler”.
If for some reason you have difficulty with the above commands, you can install the BrailleR package using a zip file version available from a CRAN repository or the latest version on GitHub.
From time to time, you should check that you are using the most recent version of the BrailleR package. You can update all installed packages using the commands:
chooseCRANmirror(ind=1)
update.packages(ask=FALSE)Once you’ve got the package installed, you still need to get it running in your current R session by issuing one last command. When you issue the first of the following lines, the package start messages will also appear.
library(BrailleR)You’re ready to go!
3.3.1 Some initial setting up instructions
When you first use the library(BrailleR) command, you will see some start up messages and a question. The rules of R packages include not writing to the user’s hard drive without expressly asking them for permission to do so. If you do not want a folder for your BrailleR files then use the temporary folder which will be removed when you end your R session. This will mean you need to answer the question over the location of the MyBrailleR folder next time you issue the library(BrailleR) command though.
The welcome message from BrailleR suggests you issue the GetGoing() command. This will ask you a few questions that will help personalise your use of the BrailleR package. We will see how to alter these settings in Chapter 8 later so don’t panic if you don’t do it all right the first time. You can re-issue the GetGoing() command again at any time.
The book you are reading now can be reached from your R session by issuing the command BrailleRInAction(). That might seem a bit much, but do remember you can use tab completion to avoid typing the whole command name out in full. You will probably need no more than B, r, a, then tab (which adds the rest of BrailleR), then I and one last tab; add the opening and closing parentheses and press the Enter key. This will open the front page of the book in your browser. A similar command, BrailleRHome(), will open the BrailleR Project home page. You will need to be careful with upper versus lower case when entering commands. Note that there are often capitalised letters in the middle of BrailleR commands. This is known as “camel case” and it works well for screen reader users.
It is all too easy to feel you’re doing it on your own, which even the most accomplished people have experienced. I put the ThankYou() command in the BrailleR package so that it would be easy to send me a message to tell me about your experiences as a blind person using R or to ask for help; it starts an email message to me. I’m not the only blind person out there using R, and many of us are on an email list so that we can share ideas and solutions for problems, many of which are specific to blind users. The JoinBlindRUG() command will start the email needed to join the BlindRUG email list.
3.4 What else do you need?
You obviously have R installed or an intention to do so soon if you are reading this document. Aside from R and the add-on packages that BrailleR needs, there are no other software requirements. There are several optional software installations that could make life easier if they are installed before you need them. In order of necessity, they are:
3.4.1 The document converter — pandoc
BrailleR requires the very useful file converter called pandoc. Get it from the pandoc download page
3.4.2 The principal integrated development environment — RStudio
It is a good idea to install RStudio, even if you can’t actually use it as a blind person using screen reading software. The reason is that RStudio installs a few other useful tools that we will make use of by other means. Get it from the RStudio download page
3.4.3 One programming language — Python
WriteR is a simple text editor written in wxPython that needs Python and wxPython. Unfortunately, they require separate downloads. You do not need this editor so do not install Python unless you are really keen. Windows users can obtain an executable file by issuing GetWriteR() once the BrailleR package has been successfully installed. More on this in Chapter 11.
3.5 BrailleR commands used in this chapter
The only BrailleR command actually recommended in this chapter was GetGoing(). You might find it useful to use BrailleRHome() and BrailleRInAction() from time to time, but you’re already reading the book that the second of these commands opens.
The ThankYou() and JoinBlindRUG() commands should be used when you want to connect with me, or other blind R users.
At this stage it is recommended that you install any additional software manually when it is required.