Returns the logical value 1.

Tests x. Returns 1 (true) if x is a text string or text cell; returns 0 (false) if x is a value, NA, ERR, or blank cell.

Returns 1 (true) if a text string is a defined range name; returns 0 (false) if it is not.

Tests x. Returns 1 (true) if x is a value or a blank cell; returns 0 (false) if x is a text string or a range.

Tests x for the value NA. Returns 1 (true) if x is the value NA; returns 0 (false) if x is not the value NA.

Tests x for the value ERR. Returns 1 (true) if x is the value ERR; returns 0 (false) if x is not the value ERR.

Returns one value (x) if a condition is true, and another value (y) if the condition is false.

Returns the logical value 0 (false).