Message-ID: <4B0D2E88.9020202@stats.uwo.ca>
Date: 2009-11-25T13:18:00Z
From: Duncan Murdoch
Subject: Test Binary File
In-Reply-To: <982584.590.qm@web56006.mail.re3.yahoo.com>
On 25/11/2009 7:34 AM, Jason Rupert wrote:
> I've got an error with the way I'm using readBin on a binary file of unknown internal structure. I know the structure consists of rows and columns, but I'm not sure how many of each.
>
> So, does anyone know of a valid test set of binary data that I could reference while trying to figure out the technique of using readBin?
>
> It would be really helpful to try out readBin on a readily available and understood binary file instead of starting with one of dubious internal structure.
>
You can write your own. For example,
f <- tempfile()
writeBin(as.numeric(1:100), f)
The hexView package is very nice for seeing what you've got:
library(hexView)
viewRaw(f)
which will show something like this:
0 : 00 00 00 00 00 00 f0 3f 00 00 00 00 00 00 00 40 | .......?.......@
16 : 00 00 00 00 00 00 08 40 00 00 00 00 00 00 10 40 | ....... at .......@
32 : 00 00 00 00 00 00 14 40 00 00 00 00 00 00 18 40 | ....... at .......@
...
viewRaw(f, human="real")
will show
0 : 00 00 00 00 00 00 f0 3f 00 00 00 00 00 00 00 40 | 1 2
16 : 00 00 00 00 00 00 08 40 00 00 00 00 00 00 10 40 | 3 4
32 : 00 00 00 00 00 00 14 40 00 00 00 00 00 00 18 40 | 5 6
48 : 00 00 00 00 00 00 1c 40 00 00 00 00 00 00 20 40 | 7 8
...
Duncan Murdoch