import daisy.lang._
import Real._



object Science {

  def verhulst(r: Real, K: Real, x: Real): Real = {
    require(r >= 4.0 && r <= 4.0 && K >= 1.11 && K <= 1.11 && 0.1 <= x && x <= 0.3)

    (r*x) / (1 + (x/K))

  }

  def predatorPrey(r: Real, K: Real, x: Real): Real = {
    require(r >= 4.0 && r <= 4.0 && K >= 1.11 && K <= 1.11 && 0.1 <= x && x <= 0.3)

    (r*x*x) / (1 + (x/K)*(x/K))

  }

  def carbonGas(T: Real, a: Real, b: Real, N: Real, p: Real, V: Real): Real = {
    require(T >= 300 && T <= 300 && a >= 0.401 && a <= 0.401 && b >= 42.7e-6 && b <= 42.7e-6 && N >= 1000 && N <= 1000 &&
    p >= 3.5e7 && p <= 3.5e7 && 0.1 <= V && V <= 0.5 && 0.1 < V && V < 0.5)

    val k: Real = 1.3806503e-23
    (p + a * (N / V) * (N / V)) * (V - N * b) - k * N * T

  }

}