Multi factorial #695
Multi factorial #695
Conversation
| @@ -169,6 +169,12 @@ fn test_factorial() { | |||
| expect_output("-5!", "-120"); | |||
| expect_output("-(5!)", "-120"); | |||
| expect_output("-(5)!", "-120"); | |||
| expect_output("5!!", "15"); | |||
There was a problem hiding this comment.
Can we expand at least the double-factorial tests a bit more and include some edge cases, as well as an example for even numbers. And maybe we could write the tests in a way that it's easy to see that we get the desired result. By moving them to a Numbat-source test suite? Something like
assert_eq(7!!, 7 * 5 * 3 * 1)
assert_eq(8!!, 8 * 4 * 2)
There was a problem hiding this comment.
Hey, that should be done in fb066f0
Could you confirm me that we cannot write an assert in a function in numbat currently?
I wanted to write a more « procedural » test with a recursive function that assert at each step that the function works on all numbers from 0 to 10 with multiple orders but then I didn’t see how to do it 🤔
There was a problem hiding this comment.
I can confirm that it isn't currently possible. I wanted to make a function to encapsulate a repeating pattern in the tests I wrote and learned it wasn't possible yet.
There was some talk about the possibility of numbat having macros for such cases, but that's still just an idea.
Hey, currently numbat doesn't handle multifactorial correctly, see the following screenshot:
This should in fact returns (5 * 3 * 1): https://en.wikipedia.org/wiki/Double_factorial#Generalizations
This PR adds support for all multifactorial, it's a breaking change though since numbat was already accepting the expression.