1) Using Numeric Functions to create a Horizontal Abstraction.

This Blog entry is from the Loading, Shaping and Merging Data section in Learn R.

As introduced R has a plethora of Blog entries that facilitate the creation of Vectors and Matrices, furthermore there are base numeric operators which facilitate:

·         + Addition.

·         - Subtraction.

·         * Multiplication.

·         / Division.

·         %% Exponent.

·         ^ Power Of.

Functions also provide the ability to perform mathematical operations.  In this example, a vector of double values will be created then rounded.  Create a new script and start by creating a vector containing double values:

Double <- c(1.22341,5.889988,6.9999890)
a-script-to-create-a-float-double-vector-in-r.png

Run the line of script to console:

a-float-double-vector-having-been-created-in-r-console.png

Use the round() function,  which takes two arguments of value and digits, to round the Double vector to two decimal places assigning that vector:

round(Double,2)
a-script-to-use-the-round-function-on-a-float-vector-in-r.png

Run the line of script to console:

a-float-double-vector-rounded-written-out-to-r-console.png

Write out the DoubleRound vector by typing:

DoubleRound
a-script-to-request-that-a-double-vector-is-written-out-to-r-console.png

Run the line of script to console:

writing-out-a-double-float-vector-to-the-r-console.png

It can be observed that the vector has been rounded to two decimal places.  By way of further abstraction find the square root:

DoubleRoundSqrt(VectorRound)
a-script-to-improve-accuracy-of-a-vector-or-variable-with-sqrt-in-r.png

Run the line of script to console:

sqrt-function-being-executed-on-a-vector-in-r-console.png

A more concise way to create a line of script relying on several functions, could include nesting the functions:

DoubleNested <- sqrt(round(Double,2))

a-script-to-embed-the-round-function-inside-the-sqrt-function-in-r.png

Run the line of script to console:

a-script-to-embed-the-round-function-inside-the-sqrt-function-in-r-executed-in-console.png

It can be observed that with the help of several R numeric functions that complex horizontal abstractions can take place.