schrodinger.kernel.LogNormal.scala Maven / Gradle / Ivy
/*
* Copyright 2021 Arman Bilge
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package schrodinger.kernel
import cats.Functor
import cats.syntax.all.*
trait LogNormal[F[_], A]:
def logNormal: F[A]
def logNormal(mu: A, sigma: A): F[A]
object LogNormal:
inline def apply[F[_], A](mu: A, sigma: A)(using ln: LogNormal[F, A]): F[A] =
ln.logNormal(mu, sigma)
inline def standard[F[_], A](using ln: LogNormal[F, A]): F[A] =
ln.logNormal
given [F[_]: Functor](using Gaussian[F, Double]): LogNormal[F, Double] with
def logNormal = Gaussian.standard.map(Math.exp)
def logNormal(mu: Double, sigma: Double) = Gaussian(mu, sigma).map(Math.exp)