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math: fix factorial_test.v error

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yuyi 2020-04-09 10:21:11 +08:00 committed by GitHub
parent bf20b01586
commit 89b83400f5
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2 changed files with 8 additions and 8 deletions
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12
vlib/math/factorial/factorial.v
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@ -13,13 +13,13 @@ import math
pub fn factorial(n f64) f64 { pub fn factorial(n f64) f64 {
// For a large postive argument (n >= FACTORIALS.len) return max_f64 // For a large postive argument (n >= FACTORIALS.len) return max_f64
if n >= FACTORIALS.len { if n >= factorials_table.len {
return math.max_f64 return math.max_f64
} }
// Otherwise return n!. // Otherwise return n!.
if n == f64(i64(n)) && n >= 0.0 { if n == f64(i64(n)) && n >= 0.0 {
return FACTORIALS[i64(n)] return factorials_table[i64(n)]
} }
return math.gamma(n + 1.0) return math.gamma(n + 1.0)
@ -37,8 +37,8 @@ pub fn log_factorial(n f64) f64 {
if n != f64(i64(n)) { if n != f64(i64(n)) {
return math.log_gamma(n+1) return math.log_gamma(n+1)
} else if n < LOG_FACTORIALS.len { } else if n < log_factorials_table.len {
return LOG_FACTORIALS[i64(n)] return log_factorials_table[i64(n)]
} }
// Otherwise return asymptotic expansion of ln(n!). // Otherwise return asymptotic expansion of ln(n!).
@ -51,9 +51,9 @@ fn log_factorial_asymptotic_expansion(n int) f64 {
mut term := []f64 mut term := []f64
xx := f64((n + 1) * (n + 1)) xx := f64((n + 1) * (n + 1))
mut xj := f64(n + 1) mut xj := f64(n + 1)
log_factorial := log_sqrt_2pi - xj + (xj - 0.5) * math.log(xj) log_factorial := log_sqrt_2pi - xj + (xj - 0.5) * math.log(xj)
mut i := 0 mut i := 0
for i = 0; i < m; i++ { for i = 0; i < m; i++ {

4
vlib/math/factorial/factorial_tables.v
View File

@ -23,7 +23,7 @@ const (
-174611.0 / (330.0 * 20.0 * 19.0) -174611.0 / (330.0 * 20.0 * 19.0)
] ]
FACTORIALS = [ factorials_table = [
f64(1.000000000000000000000e+0), /* 0! */ f64(1.000000000000000000000e+0), /* 0! */
1.000000000000000000000e+0, /* 1! */ 1.000000000000000000000e+0, /* 1! */
2.000000000000000000000e+0, /* 2! */ 2.000000000000000000000e+0, /* 2! */
@ -197,7 +197,7 @@ const (
7.257415615307998967397e+306 /* 170! */ 7.257415615307998967397e+306 /* 170! */
] ]
LOG_FACTORIALS = [ log_factorials_table = [
f64(0.000000000000000000000e+0), /* 0! */ f64(0.000000000000000000000e+0), /* 0! */
0.000000000000000000000e+0, /* 1! */ 0.000000000000000000000e+0, /* 1! */
6.931471805599453094172e-1, /* 2! */ 6.931471805599453094172e-1, /* 2! */