diff options
Diffstat (limited to 'builtin')
| -rw-r--r-- | builtin/common/misc_helpers.lua | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/builtin/common/misc_helpers.lua b/builtin/common/misc_helpers.lua index e250b0ed1..25632b4ca 100644 --- a/builtin/common/misc_helpers.lua +++ b/builtin/common/misc_helpers.lua @@ -244,6 +244,20 @@ function math.sign(x, tolerance) end -------------------------------------------------------------------------------- +function math.factorial(x) + assert(x % 1 == 0 and x >= 0, "factorial expects a non-negative integer") + if x >= 171 then + -- 171! is greater than the biggest double, no need to calculate + return math.huge + end + local v = 1 + for k = 2, x do + v = v * k + end + return v +end + +-------------------------------------------------------------------------------- function get_last_folder(text,count) local parts = text:split(DIR_DELIM) |