Using the IS Information Functions

USING THE IS INFORMATION FUNCTIONS

You can use the ISBLANK, ISERR, ISERROR, ISLOGICAL, ISNA, ISNONTEXT, ISNUMBER, ISREF, and ISTEXT functions to determine whether a referenced cell or range contains the corresponding type of value. In addition, the ISEVEN and ISODD functions are available if you’ve installed the Analysis ToolPak.

All IS Information functions take a single argument. For example, the ISBLANK function takes the form =ISBLANK(value). The value argument is a reference to a cell. If value refers to a blank cell, the function returns the logical value TRUE; otherwise, it returns FALSE.

An ISERR Example

You can use ISERR to avoid getting error values as formula results.

For example, suppose you want to call attention to cells containing a particular character string, such as 12A, resulting in the word Yes appearing in the cell containing the formula. If the string isn’t found, you want the cell to remain empty. You can use the IF and FIND functions to perform this task, but if the value isn’t found, you get a #VALUE! error rather than a blank cell.

To solve this problem, add an ISERR function to the formula. The FIND function returns the position at which a substring is found within a larger string. If the substring isn’t there, FIND returns #VALUE!. The solution is to add an ISERR function, such as =IF(ISERR(FIND("12A", A1)), " ", "Yes"). Because you’re not interested in the error, which is simply a by-product of the calculation, this traps the error, leaving only the results that you are interested in. Note When you enter numeric values as text, such as ="21", the IS function, unlike other functions, does not recognize them as numbers. Therefore, the formula =ISNUMBER(" 21") returns FALSE.