github.com/rstandt/terraform@v0.12.32-0.20230710220336-b1063613405c/website/docs/configuration/functions/log.html.md (about) 1 --- 2 layout: "functions" 3 page_title: "log - Functions - Configuration Language" 4 sidebar_current: "docs-funcs-numeric-log" 5 description: |- 6 The log function returns the logarithm of a given number in a given base. 7 --- 8 9 # `log` Function 10 11 -> **Note:** This page is about Terraform 0.12 and later. For Terraform 0.11 and 12 earlier, see 13 [0.11 Configuration Language: Interpolation Syntax](../../configuration-0-11/interpolation.html). 14 15 `log` returns the logarithm of a given number in a given base. 16 17 ```hcl 18 log(number, base) 19 ``` 20 21 ## Examples 22 23 ``` 24 > log(50, 10) 25 1.6989700043360185 26 > log(16, 2) 27 4 28 ``` 29 30 `log` and `ceil` can be used together to find the minimum number of binary 31 digits required to represent a given number of distinct values: 32 33 ``` 34 > ceil(log(15, 2)) 35 4 36 > ceil(log(16, 2)) 37 4 38 > ceil(log(17, 2)) 39 5 40 ```