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Value assignment to name in R

 Like other programming languages, the value can be assigned to name variables in R.  The assignment of a value to variable can be done as below. 

> y <- 12

> y

[1] 12

'=' can be also be used in place of '<-'. If '<-' is used, there should not be any space between two characters.

The name can be chosen from letter, digits and period symbol. But the name should not be started with a digit or period followed by a digit.

> 1. = 5

Error in 1 = 5 : invalid (do_set) left-hand side to assignment.

> .1 = 1

Error in 0.1 = 1 : invalid (do_set) left-hand side to assignment

Some characters are used already for defining functions. However, it would cause confusion if it is used for assigning a value. Few of the defined function characters are c, q, t , F, T etc.

c - Combine values into a vector or list

q - Terminate the current R session

t - Return a transpose of the given matrix

F & T - Logical argument TRUE or FALSE

Except F & T, other characters won't cause any trouble when they are assigned with value. 

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