Page 188 - Data Science Algorithms in a Week

R Reference

rectangle_side_a, "and", rectangle_side_b, "cm.\n")
cat("Then the area of the rectangle is", rectangle_area, "cm squared.\n")
cat("The perimeter of the rectangle is", rectangle_perimeter, "cm.\n")
Output:

$ Rscript example02_int.r
Let there be a rectangle with the sides of lengths: 10 and 5 cm.
Then the area of the rectangle is 50 cm squared.
The perimeter of the rectangle is 30 cm.

Numeric

The numeric data type can also hold non-integer rational values.

Input:

source_code/appendix_b_r/example03_numeric.r
pi = 3.14159
circle_radius = 10.2
circle_perimeter = 2 * pi * circle_radius
circle_area = pi * circle_radius * circle_radius
cat("Let there be a circle with the radius", circle_radius, "cm.\n")
cat("Then the perimeter of the circle is", circle_perimeter, "cm.\n")
cat("The area of the circle is", circle_area, "cm squared.\n")

Output:
$ Rscript example03_numeric.r
Let there be a circle with the radius 10.2 cm.
Then the perimeter of the circle is 64.08844 cm.
The area of the circle is 326.851 cm squared.

String

A string variable can be used to store text.
Input:

source_code/appendix_b_r/example04_string.r
first_name = "Satoshi"
last_name = "Nakamoto"
#String concatenation is performed with the command paste.
full_name = paste(first_name, last_name, sep = " ", collapse = NULL)
cat("The invertor of Bitcoin is", full_name, ".\n")

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