Introduction to the PostgreSQL EXP() function

An exponential of a number is the number e, approximately equal to2.71, raised to a given power (en).

In PostgreSQL, you can use theEXP() function to calculate the exponential of a number.

Here’s the syntax of theEXP() function:

EXP(n)

In this syntax:

• n is the number that you want to calculate the exponential. It can be a literal number, an expression, or a table column.

TheEXP() function returns the exponential of a number in double precision. TheEXP() function returnsNULL if the n isNULL.

If n is a string, theEXP() function will attempt to convert it to a number before calculating the exponential. If the conversion fails, theEXP() function will raise an error.

PostgreSQL EXP() function examples

Let’s take some examples to practice theEXP() function.

1) Basic EXP() function examples

The following example uses theEXP() function to return the exponential of 1:

SELECT EXP(1) result;

Output:

result------------------- 2.718281828459045(1 row)

It returns the Euler number (e) because e1 is e.

The following statement uses theEXP() function to return the exponential of zero:

SELECT EXP(0) result;

Output:

result--------      1(1 row)

It returns 1 because e0 is 1.

2) Using the EXP() function with numeric strings

The following example uses theEXP() function with a numeric string:

SELECT EXP('10') result;

Output:

exp-------------------- 22026.465794806718(1 row)

In this example, the EXP() function converts the string ’10’ to the number 10 before calculating the exponential of 10.

The following example raises an error because the function fails to convert the string ’10x’ to a number:

SELECT EXP('10X')result;

Error:

ERROR:  invalid input syntax for type double precision: "10X"LINE 1: SELECT EXP('10X')result;                   ^

Summary

• Use theEXP() function to calculate the exponential of a number.

Last updated onApril 18, 2024

On this page

• Introduction to the PostgreSQL EXP() function
• PostgreSQL EXP() function examples
• Summary