**Logical Operators and Comparisons**

The following table shows the operations and functions for logical comparisons (True or False).

**Examples :**

> x = 1 : 6 # Generates x=1,2,3,4,5,6

> (x > 2) & (x < 5) # Checks whether the values are greater than 2 and less than 5

[1] FALSE FALSE TRUE TRUE FALSE FALSE

> x [(x > 2) & (x < 5)] # Finds which values are greater than 2 and smaller than 5.

[1] 3 4

**Logical Operators and Comparisons**

- The
__shoter form__performs element-wise comparisons in almost the same way as arithmetic operators. - The
__longer from__evaluates left to right examining only the first element of each vector. Evaluation proceeds only until the result is determined.

> x = 1 : 6 # Generates x = 1,2,3,4,5,6

> (x > 2) && (x < 5)

[1] FALSE

is equivalent to:

> (x[1] > 2) & (x[1] < 5)

[1] FALSE

Note that x[1] is only the first element in x.

> x[ (x > 2) && (x < 5) ]

integer(0) # Finds which values are greater than 2 and smaller than 5

This statement is equivalent to

> x [ (x[1] > 2) & (x[1] < 5) ]

integer (0)

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