Skip to content

Negative numbers can't be primes by definition. #187

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
ikataitsev wants to merge 1 commit into from
Closed

Negative numbers can't be primes by definition. #187

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Negative numbers can't be primes by definition.
  • Loading branch information
@ikataitsev
ikataitsev committed Sep 21, 2012
commit f8d85d2aefb0038d8e18706775aab4168ad99eee
1 change: 0 additions & 1 deletion lib/prime.rb
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -157,7 +157,6 @@ def each(ubound = nil, generator = EratosthenesGenerator.new, &block)
# +value+:: an arbitrary integer to be checked.
# +generator+:: optional. A pseudo-prime generator.
def prime?(value, generator = Prime::Generator23.new)
value = -value if value < 0
return false if value < 2
for num in generator
q,r = value.divmod num
Expand Down
4 changes: 2 additions & 2 deletions test/test_prime.rb
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -141,8 +141,8 @@ def test_prime?

# negative
assert !-1.prime?
assert(-2.prime?)
assert(-3.prime?)
assert !-2.prime?
assert !-3.prime?
assert !-4.prime?
end
end
Expand Down