Function to calculate the derivative of the drawdown with respect to the derivative of log time using kernel regression of the measured data.

log_derivative_kernelreg(t, s, bw = NULL, return.pos = T, log = T)

Arguments

t

Numeric vector with the time

s

Numeric vector with the drawdown

bw

bandwidth

return.pos

Logical flag to return only the positive values of the log-derivative (default = TRUE)

log

Logical flag to indicate that natural logarithm (a log to the base e) is used in the derivative calculation (default = TRUE). Logarithm to the base 10 is used if FALSE.

Value

A list with

  • x: Numeric vector with the x coordinates where the log-derivative is evaluated

  • y: Numeric vector with the value of the log-derivative

  • res: Kernel regression object

See also

Examples

data(boulton) t <- boulton$t s <- boulton$s ptest <- pumping_test('Well1', Q = 0.03, r = 20, t = t, s = s) # dptest.ks <- log_derivative_kernelreg(ptest$t, ptest$s) plot(t,s,type="p",log="xy",ylim=c(1e-3,2))
lines(dptest.ks$x,dptest.ks$y,col="red")