Cast / Convert String to Decimal type

Support
1

I have a string that is pulled from external dataset/pre-load file which returns a decimal e.g. 22.5, I need to convert this string to decimal type for comparisons (>, < etc). For instance, to convert a string to integer we typically use int(), can't seem to find similar for decimal type here

2

It's there, please, see number() function https://docs.getodk.org/form-operators-functions/#number.