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Code Issues Projects Releases Packages Wiki Activity Actions 17

NormalDist.inv_cdf(): In-line constants because the variable names were not informative (GH-12446)

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Raymond Hettinger 2019-03-19 12:48:04 -07:00 • committed by Miss Islington (bot)
parent fc96e5474a
commit 52a594bd0d
1 changed files with 47 additions and 60 deletions
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107
Lib/statistics.py
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@ -766,74 +766,61 @@ class NormalDist:
q = p - 0.5 q = p - 0.5
if fabs(q) <= 0.425: if fabs(q) <= 0.425:
a0 = 3.38713_28727_96366_6080e+0
a1 = 1.33141_66789_17843_7745e+2
a2 = 1.97159_09503_06551_4427e+3
a3 = 1.37316_93765_50946_1125e+4
a4 = 4.59219_53931_54987_1457e+4
a5 = 6.72657_70927_00870_0853e+4
a6 = 3.34305_75583_58812_8105e+4
a7 = 2.50908_09287_30122_6727e+3
b1 = 4.23133_30701_60091_1252e+1
b2 = 6.87187_00749_20579_0830e+2
b3 = 5.39419_60214_24751_1077e+3
b4 = 2.12137_94301_58659_5867e+4
b5 = 3.93078_95800_09271_0610e+4
b6 = 2.87290_85735_72194_2674e+4
b7 = 5.22649_52788_52854_5610e+3
r = 0.180625 - q * q r = 0.180625 - q * q
num = (q * (((((((a7 * r + a6) * r + a5) * r + a4) * r + a3) num = (q * (((((((2.50908_09287_30122_6727e+3 * r +
* r + a2) * r + a1) * r + a0)) 3.34305_75583_58812_8105e+4) * r +
den = ((((((((b7 * r + b6) * r + b5) * r + b4) * r + b3) 6.72657_70927_00870_0853e+4) * r +
* r + b2) * r + b1) * r + 1.0)) 4.59219_53931_54987_1457e+4) * r +
1.37316_93765_50946_1125e+4) * r +
1.97159_09503_06551_4427e+3) * r +
1.33141_66789_17843_7745e+2) * r +
3.38713_28727_96366_6080e+0))
den = ((((((((5.22649_52788_52854_5610e+3 * r +
2.87290_85735_72194_2674e+4) * r +
3.93078_95800_09271_0610e+4) * r +
2.12137_94301_58659_5867e+4) * r +
5.39419_60214_24751_1077e+3) * r +
6.87187_00749_20579_0830e+2) * r +
4.23133_30701_60091_1252e+1) * r + 1.0))
x = num / den x = num / den
return self.mu + (x * self.sigma) return self.mu + (x * self.sigma)
r = p if q <= 0.0 else 1.0 - p r = p if q <= 0.0 else 1.0 - p
r = sqrt(-log(r)) r = sqrt(-log(r))
if r <= 5.0: if r <= 5.0:
c0 = 1.42343_71107_49683_57734e+0
c1 = 4.63033_78461_56545_29590e+0
c2 = 5.76949_72214_60691_40550e+0
c3 = 3.64784_83247_63204_60504e+0
c4 = 1.27045_82524_52368_38258e+0
c5 = 2.41780_72517_74506_11770e-1
c6 = 2.27238_44989_26918_45833e-2
c7 = 7.74545_01427_83414_07640e-4
d1 = 2.05319_16266_37758_82187e+0
d2 = 1.67638_48301_83803_84940e+0
d3 = 6.89767_33498_51000_04550e-1
d4 = 1.48103_97642_74800_74590e-1
d5 = 1.51986_66563_61645_71966e-2
d6 = 5.47593_80849_95344_94600e-4
d7 = 1.05075_00716_44416_84324e-9
r = r - 1.6 r = r - 1.6
num = ((((((((c7 * r + c6) * r + c5) * r + c4) * r + c3) num = ((((((((7.74545_01427_83414_07640e-4 * r +
* r + c2) * r + c1) * r + c0)) 2.27238_44989_26918_45833e-2) * r +
den = ((((((((d7 * r + d6) * r + d5) * r + d4) * r + d3) 2.41780_72517_74506_11770e-1) * r +
* r + d2) * r + d1) * r + 1.0)) 1.27045_82524_52368_38258e+0) * r +
else: 3.64784_83247_63204_60504e+0) * r +
e0 = 6.65790_46435_01103_77720e+0 5.76949_72214_60691_40550e+0) * r +
e1 = 5.46378_49111_64114_36990e+0 4.63033_78461_56545_29590e+0) * r +
e2 = 1.78482_65399_17291_33580e+0 1.42343_71107_49683_57734e+0))
e3 = 2.96560_57182_85048_91230e-1
e4 = 2.65321_89526_57612_30930e-2
e5 = 1.24266_09473_88078_43860e-3
e6 = 2.71155_55687_43487_57815e-5
e7 = 2.01033_43992_92288_13265e-7
f1 = 5.99832_20655_58879_37690e-1
f2 = 1.36929_88092_27358_05310e-1
f3 = 1.48753_61290_85061_48525e-2
f4 = 7.86869_13114_56132_59100e-4
f5 = 1.84631_83175_10054_68180e-5
f6 = 1.42151_17583_16445_88870e-7
f7 = 2.04426_31033_89939_78564e-15
r = r - 5.0
num = ((((((((e7 * r + e6) * r + e5) * r + e4) * r + e3)
* r + e2) * r + e1) * r + e0))
den = ((((((((f7 * r + f6) * r + f5) * r + f4) * r + f3)
* r + f2) * r + f1) * r + 1.0))
den = ((((((((1.05075_00716_44416_84324e-9 * r +
5.47593_80849_95344_94600e-4) * r +
1.51986_66563_61645_71966e-2) * r +
1.48103_97642_74800_74590e-1) * r +
6.89767_33498_51000_04550e-1) * r +
1.67638_48301_83803_84940e+0) * r +
2.05319_16266_37758_82187e+0) * r + 1.0))
else:
r = r - 5.0
num = ((((((((2.01033_43992_92288_13265e-7 * r +
2.71155_55687_43487_57815e-5) * r +
1.24266_09473_88078_43860e-3) * r +
2.65321_89526_57612_30930e-2) * r +
2.96560_57182_85048_91230e-1) * r +
1.78482_65399_17291_33580e+0) * r +
5.46378_49111_64114_36990e+0) * r +
6.65790_46435_01103_77720e+0))
den = ((((((((2.04426_31033_89939_78564e-15 * r +
1.42151_17583_16445_88870e-7) * r +
1.84631_83175_10054_68180e-5) * r +
7.86869_13114_56132_59100e-4) * r +
1.48753_61290_85061_48525e-2) * r +
1.36929_88092_27358_05310e-1) * r +
5.99832_20655_58879_37690e-1) * r + 1.0))
x = num / den x = num / den
if q < 0.0: if q < 0.0:
x = -x x = -x