Function to calculate the flow dimension using different approaches
flow_dimension(t, s, d = 2, method = "central")
Arguments
| t | Numeric vector with time values |
|---|---|
| s | Numeric vector with drawdown values |
| d | Derivative parameter. if method equals to bourdet then d is equal to the number of adjacent values used in the derivative calculation. If method is equal to spline then d is equal to the number of knots used in the interpolation of the drawdown data. In this case a value of d=20 to d=30 is recommended. If method is equal to spane then d is equal to the number of points used in the linear regression approach. |
| method | Method to calculate the derivative. See log_derivative |
Value
This function returns a list with components:
x: Numeric vector with times at which the second derivative is evaluated
y: Numeric vector with the values of the second derivative of drawdown
n: Numeric vector with the flow dimension values evaluated at each time
Examples
data(boulton) t <- boulton$t s <- boulton$s boulton.fdim <- flow_dimension(t,s, method = "smoothspline") plot(boulton.fdim$x, boulton.fdim$n, type = "p", log = "x", ylim = c(0, 10))
