DATA MINING
Desktop Survival Guide by Graham Williams |
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Interactive Data Entry |
To interactively load some data into a vector we can use the
scan function which can, for example, read data you type
until it finds an empty line:
> ds <- scan() 1: 54 56 57 59 5: 63 64 66 68 9: Read 8 items > ds [1] 54 56 57 59 63 64 66 68 |
Alternatively, we may have a simple list of numbers in one of our
windows on the screen and simply wish to load this into R. For
example, select the list of numbers below, assuming we are reading
this document on the screen (e.g., we hold down the left mouse button
while highlighting the list of numbers):
54 56 57 59 63 64 66 68 68 72 72 75 76 81 84 88 106 |
> ds <- scan("clipboard") Read 17 items > ds [1] 54 56 57 59 63 64 66 68 68 72 72 75 76 81 84 88 106 |
All of the above read the data into a vector. An alternative is to load data into a data frame. Similar approaches are possible. Suppose we have this height and weight data for 30 eleven year old girls attending Heaton Middle School, Bradford UK (http://www.sci.usq.edu.au/staff/dunn/Datasets/Books/Hand/Hand-R/height-R.html, Hand 96).
Height Weight 135 26 146 33 153 55 154 50 139 32 131 25 149 44 137 31 143 36 146 35 141 28 136 28 154 36 151 48 155 36 133 31 149 34 141 32 164 47 146 37 149 46 147 36 152 47 140 33 143 42 148 32 149 32 141 29 137 34 135 30 |
We can also place the data into a string within R and read the data
from directly from the string:
lines <- "Height 54 56 57 59 63 64 66 68 68 72 72 75 76 81 84 88 106 " ds <- read.table(textConnection(lines), header = TRUE) |
Another example, reading a table of data:
x <- "Obs SD Mean 1 1.5 6 2 0.3 8" obs <- read.table(textConnection(x), header=TRUE, as.is=TRUE) plot(1:10, type="n" ) text(c(1.2, 2, 3), 8, labels=names(xx), cex=.7) arrows(.75,7.75, 3.5, 7.75, length=0) text(c(1.2, 2, 3), 7.5, labels=xx[1,], cex=.7) text(c(1.2, 2, 3), 7.0, labels=xx[2,], cex=.7) arrows(.75, 6.75,3.5, 6.75, length=0) |
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