diff --git a/Cargo.toml b/Cargo.toml
index e291172..44fa244 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,8 +6,8 @@ edition = "2018"
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-lapacke = "0.2"
-ndarray = { version = "0.14", features = ["approx"] }
+lapacke = "0.5"
+ndarray = { version = "0.15", features = ["approx"] }
 
 [dev-dependencies]
 approx = "0.4"
diff --git a/src/kernel/affine.rs b/src/kernel/affine.rs
index c904932..94f1c6c 100644
--- a/src/kernel/affine.rs
+++ b/src/kernel/affine.rs
@@ -1,5 +1,3 @@
-use std::iter::FromIterator;
-
 use ndarray::prelude::*;
 
 use super::Kernel;
@@ -36,7 +34,7 @@ impl Kernel for Affine {
     }
 
     fn k_diag(&self, ts: &[f64]) -> Array1<f64> {
-        let r = Array1::from_iter(ts.iter().map(|v| (v - self.t0).powi(2)));
+        let r: Array1<_> = ts.iter().map(|v| (v - self.t0).powi(2)).collect();
 
         (r * self.var_slope) + self.var_offset
     }
diff --git a/src/kernel/wiener.rs b/src/kernel/wiener.rs
index ada3721..2d84abc 100644
--- a/src/kernel/wiener.rs
+++ b/src/kernel/wiener.rs
@@ -1,5 +1,3 @@
-use std::iter::FromIterator;
-
 use ndarray::prelude::*;
 
 use super::Kernel;
@@ -32,7 +30,7 @@ impl Kernel for Wiener {
     }
 
     fn k_diag(&self, ts: &[f64]) -> Array1<f64> {
-        (Array1::from_iter(ts.iter().map(|v| v - self.t0)) * self.var) + self.var_t0
+        (ts.iter().map(|v| v - self.t0).collect::<Array1<_>>() * self.var) + self.var_t0
     }
 
     fn order(&self) -> usize {
diff --git a/src/math.rs b/src/math.rs
index 65105d2..9abaaec 100644
--- a/src/math.rs
+++ b/src/math.rs
@@ -13,310 +13,310 @@ pub fn erfc(x: f64) -> f64 {
 /// Polynomial coefficients for a numerator of `erf_impl`
 /// in the interval [1e-10, 0.5].
 const ERF_IMPL_AN: &[f64] = &[
-    0.00337916709551257388990745,
-    -0.00073695653048167948530905,
-    -0.374732337392919607868241,
-    0.0817442448733587196071743,
-    -0.0421089319936548595203468,
-    0.0070165709512095756344528,
-    -0.00495091255982435110337458,
-    0.000871646599037922480317225,
+    0.003_379_167_095_512_573_7,
+    -0.000_736_956_530_481_679_5,
+    -0.374_732_337_392_919_6,
+    0.081_744_244_873_358_73,
+    -0.042_108_931_993_654_86,
+    0.007_016_570_951_209_575,
+    -0.004_950_912_559_824_351,
+    0.000_871_646_599_037_922_5,
 ];
 
 /// Polynomial coefficients for a denominator of `erf_impl`
 /// in the interval [1e-10, 0.5]
 const ERF_IMPL_AD: &[f64] = &[
     1.0,
-    -0.218088218087924645390535,
-    0.412542972725442099083918,
-    -0.0841891147873106755410271,
-    0.0655338856400241519690695,
-    -0.0120019604454941768171266,
-    0.00408165558926174048329689,
-    -0.000615900721557769691924509,
+    -0.218_088_218_087_924_64,
+    0.412_542_972_725_442_1,
+    -0.084_189_114_787_310_67,
+    0.065_533_885_640_024_16,
+    -0.012_001_960_445_494_177,
+    0.004_081_655_589_261_74,
+    -0.000_615_900_721_557_769_7,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [0.5, 0.75].
 const ERF_IMPL_BN: &[f64] = &[
-    -0.0361790390718262471360258,
-    0.292251883444882683221149,
-    0.281447041797604512774415,
-    0.125610208862766947294894,
-    0.0274135028268930549240776,
-    0.00250839672168065762786937,
+    -0.036_179_039_071_826_25,
+    0.292_251_883_444_882_7,
+    0.281_447_041_797_604_5,
+    0.125_610_208_862_766_94,
+    0.027_413_502_826_893_053,
+    0.002_508_396_721_680_657_5,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [0.5, 0.75].
 const ERF_IMPL_BD: &[f64] = &[
     1.0,
-    1.8545005897903486499845,
-    1.43575803037831418074962,
-    0.582827658753036572454135,
-    0.124810476932949746447682,
-    0.0113724176546353285778481,
+    1.854_500_589_790_348_6,
+    1.435_758_030_378_314_2,
+    0.582_827_658_753_036_5,
+    0.124_810_476_932_949_75,
+    0.011_372_417_654_635_328,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [0.75, 1.25].
 const ERF_IMPL_CN: &[f64] = &[
-    -0.0397876892611136856954425,
-    0.153165212467878293257683,
-    0.191260295600936245503129,
-    0.10276327061989304213645,
-    0.029637090615738836726027,
-    0.0046093486780275489468812,
-    0.000307607820348680180548455,
+    -0.039_787_689_261_113_69,
+    0.153_165_212_467_878_3,
+    0.191_260_295_600_936_24,
+    0.102_763_270_619_893_04,
+    0.029_637_090_615_738_836,
+    0.004_609_348_678_027_549,
+    0.000_307_607_820_348_680_2,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [0.75, 1.25].
 const ERF_IMPL_CD: &[f64] = &[
     1.0,
-    1.95520072987627704987886,
-    1.64762317199384860109595,
-    0.768238607022126250082483,
-    0.209793185936509782784315,
-    0.0319569316899913392596356,
-    0.00213363160895785378615014,
+    1.955_200_729_876_277,
+    1.647_623_171_993_848_6,
+    0.768_238_607_022_126_2,
+    0.209_793_185_936_509_78,
+    0.031_956_931_689_991_336,
+    0.002_133_631_608_957_853_7,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [1.25, 2.25].
 const ERF_IMPL_DN: &[f64] = &[
-    -0.0300838560557949717328341,
-    0.0538578829844454508530552,
-    0.0726211541651914182692959,
-    0.0367628469888049348429018,
-    0.00964629015572527529605267,
-    0.00133453480075291076745275,
-    0.778087599782504251917881e-4,
+    -0.030_083_856_055_794_972,
+    0.053_857_882_984_445_45,
+    0.072_621_154_165_191_42,
+    0.036_762_846_988_804_936,
+    0.009_646_290_155_725_275,
+    0.001_334_534_800_752_910_7,
+    7.780_875_997_825_043e-5,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [1.25, 2.25].
 const ERF_IMPL_DD: &[f64] = &[
     1.0,
-    1.75967098147167528287343,
-    1.32883571437961120556307,
-    0.552528596508757581287907,
-    0.133793056941332861912279,
-    0.0179509645176280768640766,
-    0.00104712440019937356634038,
-    -0.106640381820357337177643e-7,
+    1.759_670_981_471_675_3,
+    1.328_835_714_379_611_2,
+    0.552_528_596_508_757_6,
+    0.133_793_056_941_332_87,
+    0.017_950_964_517_628_076,
+    0.001_047_124_400_199_373_6,
+    -1.066_403_818_203_573_4e-8,
 ];
 
 ///  Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [2.25, 3.5].
 const ERF_IMPL_EN: &[f64] = &[
-    -0.0117907570137227847827732,
-    0.014262132090538809896674,
-    0.0202234435902960820020765,
-    0.00930668299990432009042239,
-    0.00213357802422065994322516,
-    0.00025022987386460102395382,
-    0.120534912219588189822126e-4,
+    -0.011_790_757_013_722_784,
+    0.014_262_132_090_538_81,
+    0.020_223_443_590_296_084,
+    0.009_306_682_999_904_321,
+    0.002_133_578_024_220_66,
+    0.000_250_229_873_864_601_05,
+    1.205_349_122_195_881_9e-5,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [2.25, 3.5].
 const ERF_IMPL_ED: &[f64] = &[
     1.0,
-    1.50376225203620482047419,
-    0.965397786204462896346934,
-    0.339265230476796681555511,
-    0.0689740649541569716897427,
-    0.00771060262491768307365526,
-    0.000371421101531069302990367,
+    1.503_762_252_036_204_8,
+    0.965_397_786_204_462_9,
+    0.339_265_230_476_796_7,
+    0.068_974_064_954_156_98,
+    0.007_710_602_624_917_683,
+    0.000_371_421_101_531_069_3,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [3.5, 5.25].
 const ERF_IMPL_FN: &[f64] = &[
-    -0.00546954795538729307482955,
-    0.00404190278731707110245394,
-    0.0054963369553161170521356,
-    0.00212616472603945399437862,
-    0.000394984014495083900689956,
-    0.365565477064442377259271e-4,
-    0.135485897109932323253786e-5,
+    -0.005_469_547_955_387_293,
+    0.004_041_902_787_317_071,
+    0.005_496_336_955_316_117,
+    0.002_126_164_726_039_454,
+    0.000_394_984_014_495_083_9,
+    3.655_654_770_644_424e-5,
+    1.354_858_971_099_323_2e-6,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [3.5, 5.25].
 const ERF_IMPL_FD: &[f64] = &[
     1.0,
-    1.21019697773630784832251,
-    0.620914668221143886601045,
-    0.173038430661142762569515,
-    0.0276550813773432047594539,
-    0.00240625974424309709745382,
-    0.891811817251336577241006e-4,
-    -0.465528836283382684461025e-11,
+    1.210_196_977_736_307_7,
+    0.620_914_668_221_143_9,
+    0.173_038_430_661_142_77,
+    0.027_655_081_377_343_203,
+    0.002_406_259_744_243_097_3,
+    8.918_118_172_513_365e-5,
+    -4.655_288_362_833_827e-12,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [5.25, 8].
 const ERF_IMPL_GN: &[f64] = &[
-    -0.00270722535905778347999196,
-    0.0013187563425029400461378,
-    0.00119925933261002333923989,
-    0.00027849619811344664248235,
-    0.267822988218331849989363e-4,
-    0.923043672315028197865066e-6,
+    -0.002_707_225_359_057_783_7,
+    0.001_318_756_342_502_94,
+    0.001_199_259_332_610_023_3,
+    0.000_278_496_198_113_446_64,
+    2.678_229_882_183_318_6e-5,
+    9.230_436_723_150_282e-7,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [5.25, 8].
 const ERF_IMPL_GD: &[f64] = &[
     1.0,
-    0.814632808543141591118279,
-    0.268901665856299542168425,
-    0.0449877216103041118694989,
-    0.00381759663320248459168994,
-    0.000131571897888596914350697,
-    0.404815359675764138445257e-11,
+    0.814_632_808_543_141_6,
+    0.268_901_665_856_299_54,
+    0.044_987_721_610_304_114,
+    0.003_817_596_633_202_484_7,
+    0.000_131_571_897_888_596_92,
+    4.048_153_596_757_641e-12,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [8, 11.5].
 const ERF_IMPL_HN: &[f64] = &[
-    -0.00109946720691742196814323,
-    0.000406425442750422675169153,
-    0.000274499489416900707787024,
-    0.465293770646659383436343e-4,
-    0.320955425395767463401993e-5,
-    0.778286018145020892261936e-7,
+    -0.001_099_467_206_917_422,
+    0.000_406_425_442_750_422_67,
+    0.000_274_499_489_416_900_7,
+    4.652_937_706_466_594e-5,
+    3.209_554_253_957_674_6e-6,
+    7.782_860_181_450_209e-8,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [8, 11.5].
 const ERF_IMPL_HD: &[f64] = &[
     1.0,
-    0.588173710611846046373373,
-    0.139363331289409746077541,
-    0.0166329340417083678763028,
-    0.00100023921310234908642639,
-    0.24254837521587225125068e-4,
+    0.588_173_710_611_846_1,
+    0.139_363_331_289_409_75,
+    0.016_632_934_041_708_368,
+    0.001_000_239_213_102_349_1,
+    2.425_483_752_158_722_4e-5,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [11.5, 17].
 const ERF_IMPL_IN: &[f64] = &[
-    -0.00056907993601094962855594,
-    0.000169498540373762264416984,
-    0.518472354581100890120501e-4,
-    0.382819312231928859704678e-5,
-    0.824989931281894431781794e-7,
+    -0.000_569_079_936_010_949_6,
+    0.000_169_498_540_373_762_25,
+    5.184_723_545_811_009e-5,
+    3.828_193_122_319_288_5e-6,
+    8.249_899_312_818_944e-8,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [11.5, 17].
 const ERF_IMPL_ID: &[f64] = &[
     1.0,
-    0.339637250051139347430323,
-    0.043472647870310663055044,
-    0.00248549335224637114641629,
-    0.535633305337152900549536e-4,
-    -0.117490944405459578783846e-12,
+    0.339_637_250_051_139_37,
+    0.043_472_647_870_310_66,
+    0.002_485_493_352_246_371,
+    5.356_333_053_371_529e-5,
+    -1.174_909_444_054_595_8e-13,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [17, 24].
 const ERF_IMPL_JN: &[f64] = &[
-    -0.000241313599483991337479091,
-    0.574224975202501512365975e-4,
-    0.115998962927383778460557e-4,
-    0.581762134402593739370875e-6,
-    0.853971555085673614607418e-8,
+    -0.000_241_313_599_483_991_34,
+    5.742_249_752_025_015e-5,
+    1.159_989_629_273_837_7e-5,
+    5.817_621_344_025_938e-7,
+    8.539_715_550_856_736e-9,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [17, 24].
 const ERF_IMPL_JD: &[f64] = &[
     1.0,
-    0.233044138299687841018015,
-    0.0204186940546440312625597,
-    0.000797185647564398289151125,
-    0.117019281670172327758019e-4,
+    0.233_044_138_299_687_84,
+    0.020_418_694_054_644_03,
+    0.000_797_185_647_564_398_3,
+    1.170_192_816_701_723_2e-5,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [24, 38].
 const ERF_IMPL_KN: &[f64] = &[
-    -0.000146674699277760365803642,
-    0.162666552112280519955647e-4,
-    0.269116248509165239294897e-5,
-    0.979584479468091935086972e-7,
-    0.101994647625723465722285e-8,
+    -0.000_146_674_699_277_760_36,
+    1.626_665_521_122_805_3e-5,
+    2.691_162_485_091_652_3e-6,
+    9.795_844_794_680_92e-8,
+    1.019_946_476_257_234_6e-9,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [24, 38].
 const ERF_IMPL_KD: &[f64] = &[
     1.0,
-    0.165907812944847226546036,
-    0.0103361716191505884359634,
-    0.000286593026373868366935721,
-    0.298401570840900340874568e-5,
+    0.165_907_812_944_847_22,
+    0.010_336_171_619_150_588,
+    0.000_286_593_026_373_868_4,
+    2.984_015_708_409_003_4e-6,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [38, 60].
 const ERF_IMPL_LN: &[f64] = &[
-    -0.583905797629771786720406e-4,
-    0.412510325105496173512992e-5,
-    0.431790922420250949096906e-6,
-    0.993365155590013193345569e-8,
-    0.653480510020104699270084e-10,
+    -5.839_057_976_297_718e-5,
+    4.125_103_251_054_962e-6,
+    4.317_909_224_202_509_4e-7,
+    9.933_651_555_900_132e-9,
+    6.534_805_100_201_047e-11,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [38, 60].
 const ERF_IMPL_LD: &[f64] = &[
     1.0,
-    0.105077086072039915406159,
-    0.00414278428675475620830226,
-    0.726338754644523769144108e-4,
-    0.477818471047398785369849e-6,
+    0.105_077_086_072_039_92,
+    0.004_142_784_286_754_756,
+    7.263_387_546_445_238e-5,
+    4.778_184_710_473_988e-7,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [60, 85].
 const ERF_IMPL_MN: &[f64] = &[
-    -0.196457797609229579459841e-4,
-    0.157243887666800692441195e-5,
-    0.543902511192700878690335e-7,
-    0.317472492369117710852685e-9,
+    -1.964_577_976_092_295_8e-5,
+    1.572_438_876_668_007e-6,
+    5.439_025_111_927_009e-8,
+    3.174_724_923_691_177e-10,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [60, 85].
 const ERF_IMPL_MD: &[f64] = &[
     1.0,
-    0.052803989240957632204885,
-    0.000926876069151753290378112,
-    0.541011723226630257077328e-5,
-    0.535093845803642394908747e-15,
+    0.052_803_989_240_957_63,
+    0.000_926_876_069_151_753_3,
+    5.410_117_232_266_303e-6,
+    5.350_938_458_036_424e-16,
 ];
 
 /// Polynomial coefficients for a numerator in `erf_impl`
 /// in the interval [85, 110].
 const ERF_IMPL_NN: &[f64] = &[
-    -0.789224703978722689089794e-5,
-    0.622088451660986955124162e-6,
-    0.145728445676882396797184e-7,
-    0.603715505542715364529243e-10,
+    -7.892_247_039_787_227e-6,
+    6.220_884_516_609_87e-7,
+    1.457_284_456_768_824e-8,
+    6.037_155_055_427_153e-11,
 ];
 
 /// Polynomial coefficients for a denominator in `erf_impl`
 /// in the interval [85, 110].
 const ERF_IMPL_ND: &[f64] = &[
     1.0,
-    0.0375328846356293715248719,
-    0.000467919535974625308126054,
-    0.193847039275845656900547e-5,
+    0.037_532_884_635_629_37,
+    0.000_467_919_535_974_625_3,
+    1.938_470_392_758_456_5e-6,
 ];
 
 /// `erf_impl` computes the error function at `z`.
@@ -334,7 +334,7 @@ fn erf_impl(z: f64, inv: bool) -> f64 {
 
     let result = if z < 0.5 {
         if z < 1e-10 {
-            z * 1.125 + z * 0.003379167095512573896158903121545171688
+            z * 1.125 + z * 0.003_379_167_095_512_573_7
         } else {
             z * 1.125 + z * polynomial(z, ERF_IMPL_AN) / polynomial(z, ERF_IMPL_AD)
         }
diff --git a/src/model/binary.rs b/src/model/binary.rs
index 48e8502..97f0041 100644
--- a/src/model/binary.rs
+++ b/src/model/binary.rs
@@ -6,6 +6,12 @@ use crate::kernel::Kernel;
 use crate::observation::*;
 use crate::storage::Storage;
 
+/*
+trait BinaryObeservation: Observation {
+    fn new(storage: &mut Storage, elems: &[(usize, f64)], t: f64, margin: f64) -> Self;
+}
+*/
+
 pub enum BinaryModelObservation {
     Probit,
     Logit,
diff --git a/src/utils.rs b/src/utils.rs
index 8868fb3..08c3964 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -20,20 +20,20 @@ const CS: [f64; 14] = [
 ];
 
 const RS: [f64; 5] = [
-    1.2753666447299659525,
-    5.019049726784267463450,
-    6.1602098531096305441,
-    7.409740605964741794425,
-    2.9788656263939928886,
+    1.275_366_644_729_965_9,
+    5.019_049_726_784_267,
+    6.160_209_853_109_631,
+    7.409_740_605_964_742,
+    2.978_865_626_393_993,
 ];
 
 const QS: [f64; 6] = [
-    2.260528520767326969592,
-    9.3960340162350541504,
-    12.048951927855129036034,
-    17.081440747466004316,
-    9.608965327192787870698,
-    3.3690752069827527677,
+    2.260_528_520_767_327,
+    9.396_034_016_235_054,
+    12.048_951_927_855_128,
+    17.081_440_747_466_004,
+    9.608_965_327_192_788,
+    3.369_075_206_982_752_8,
 ];
 
 /// Normal cumulative density function.
@@ -59,7 +59,7 @@ pub fn logphi(z: f64) -> (f64, f64) {
         (res, dres)
     } else if z < -11.3137 {
         // Second case: z very small.
-        let mut num = 0.5641895835477550741;
+        let mut num = 0.564_189_583_547_755_1;
 
         for r in &RS {
             num = -z * num / SQRT_2 + r;