log_derivative_kernelreg: log_derivative_kernelreg

In khaors/pumpingtest: R Package for the analysis and evaluation of pumping tests

Description

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

Usage

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

Author(s)

Oscar Garcia-Cabrejo [e-mail]

See Also

Other log_derivative functions: log_derivative_bourdet, log_derivative_central, log_derivative_horner, log_derivative_locpol, log_derivative_lokern, log_derivative_lpridge, log_derivative_smoothspline, log_derivative_spane, log_derivative_spline, log_derivative

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")

khaors/pumpingtest documentation built on Nov. 15, 2019, 8:10 p.m.