respace {DecomposeR}

Interpolate with even spacing

Description

Interpolate with even spacing. Can determine on its own the most conservative sampling interval (using the Greatest Common Rational Divisor)

Usage

respace(
  dt,
  xy = NULL,
  delta = NULL,
  tolerance = 8,
  relative = TRUE,
  n.warn = 100
)

Arguments

dt

depth/time (same length than length/rows of xy)

xy

signal (vector or matrix)

delta

the new sampling interval. If NULL, uses the Greatest Common Rational Divisor

tolerance, relative

parameters for the divisor function (StratigrapheR package), to compute the Greatest Common Rational Divisor

n.warn

the amount of interpolated points in between the largest interval above which a warning is provided. This warning can be useful to avoid needlessly long outputs, which might make any subsequent computation take too much time.

Value

a list of interpolated xy and dt values ($xy and $dt), plus a vector of logicals indicating whether each point was part of the initial input or was added by interpolation

Examples

set.seed(42)

n <- 50
t <- seq_len(n)

xy <- (1 + 0.6 * sin(t*0.025)) * sin(t*0.2)  + 2 * sin(t*0.025) +
        rnorm(n, sd = 0.5)

inter_dt <- round(runif(length(xy), min = 0.5, max = 1.5), 1)

dt <- cumsum(inter_dt)

res <- respace(xy = xy, dt = dt)

opar <- par("mfrow")

par(mfrow = c(1,1))

plot(res$xy, res$dt, type = "l")
points(res$xy[res$initial], res$dt[res$initial], pch = 19, col = "green")
points(res$xy[!res$initial], res$dt[!res$initial],
       pch = 19, col = "red", cex = 0.5)

par(mfrow = opar)