warpWindowSP function

Restrict the DTW warping window for snow profiles alignment

Given a matrix, this function sets all elements of the matrix that are outside the so-called warping window to NA. The warping window is a slanted band of constant width around the main diagonal (i.e., Sakoe-Chiba-band), and it's size can be controlled with function arguments.

warpWindowSP(
  iw,
  jw,
  iheight,
  jheight,
  iddate,
  jddate,
  profile.size,
  profile.height,
  window.size = 0.3,
  window.size.abs = NA,
  ddate.window.size = Inf,
  ...
)

Arguments

• iw: matrix of integers indicating their row number (cf., ?row)
• jw: matrix of integers indicating their column number (cf., ?col)
• iheight: matrix of query height filled into the columns of the matrix
• jheight: matrix of ref height filled into the rows of the matrix
• iddate: same as iheight, but containing deposition date information (i.e., POSIXct data converted to numeric through matrix call!)
• jddate: same as jheight, but containing deposition date information (i.e., POSIXct data converted to numeric through matrix call!)
• profile.size: number of layers in the longer one of the two profiles (scalar)
• profile.height: snow height of the deeper one of the two profiles (scalar)
• window.size: percentage of profile.size or profile.height defining the size of the warping window (i.e., the most restrictive of the two will be applied)
• window.size.abs: Instead of a window.size percentage, an absolute value (in cm!) can be provided
• ddate.window.size: number of days that exclude layers from the warping window if their deposition dates differ by more than these days
• ...: unused---but important to be able to provide other warping functions to distanceSPlayers

See Also

dtw::dtwWindowingFunctions