ah... I see, makes sense. Atrium has (what I named) explanatory assertions which can be used for this purpose. For instance:
https://github.com/robstoll/atrium/blob/v0.6.0/atrium-assertions/src/main/kotlin/ch/tutteli/atrium/assertions/floatingPointAssertions.kt#L37
But notice, this part isn't stable yet (whole atrium-core... as well as atrium-assertions... isn't stable yet) and I am already working at simplifying things so that I can provide a stable API. I'll deprecated most functions (I'll remove those with v1.0.0) in atrium-assertions with v0.7.0 (most likely I have to remove a few even with v0.7.0). You can use it now but would have to update it with 1.0.0 latest