# How Do Logical and Lookup Functions Differ from Mathematical Functions in Excel?

by Darrin KoltowLearning to distinguish between Excel's logical, lookup and mathematical functions helps you choose the correct function for your data-processing needs. For example, if you need to graph a function for a homework assignment in trigonometry, understanding Excel's function categories will quickly steer you to the right function. Note that Excel has other function categories besides the three considered here. Others include "financial," "text," and "date and time."

### Logical

Logical functions allow you to make comparisons, and can yield either numeric or text values based on those comparisons. For example, the formula "if (sales < 1000, "Close Business", "Stay Open")" will yield a text value based on whether the "sales" cell is less than $1,000. Since this and other logical functions can return text values, they differ from mathematical functions, which can only return numeric values.

### Lookup

Lookup functions search for and retrieve information in your workbook so you can use the information in the currently selected cell. For example, some lookup functions like "Vlookup" and "Hlookup" turn an abbreviation into longer text by looking up that abbreviation in a table you define. These functions differ from mathematical ones by yielding return values that are text, not numeric.

### Mathematical

Mathematical functions yield numbers. For example, the "Cos" function, which computes the cosine of an angle entered in radians, yields a real number ranging from 0 to 1. Math functions are available by clicking the "Math & trig" button in the "Function library" panel of the "Formulas" tab.

### Choosing Functions

Choose the correct type of function based on the type of value you require a function to yield, and based on the operation you need the function to perform. For example, if you need to find the column number of a cell named "sales," look for a function in the "Lookup" category of the "Formulas" tab, since this category's functions yield information about your workbook. If instead you need to round a number to the next highest integer, click the "Math" button on the "Formulas" tab, then click the "Roundup" function. This function's argument is a numerical value, not a comparison. Also, this function yields a number based on a mathematical computation, rather than one based on information in your workbook.

- "Excel 2010 Bible"; John Walkenbach; 2010