SAMPLE1D(l)															       SAMPLE1D(l)

NAME

       sample1d - Resampling of 1-D data sets

SYNOPSIS

       sample1d infile [ -Fl|a|c ] [ -H[nrec] ] [ -Ixinc ] [ -M[flag] ] [ -Nknotfile ] [ -Sxstart ] [ -Tx-col] [ -V ] [ -bi[s][n] ] [ -bo[s][n] ]

DESCRIPTION

       sample1d  reads	a  multi-column ASCII [or binary] data set from file [or standard input] and resamples the timeseries/profile at locations
       where the user needs the values. The user must provide the column number of the independent (monotonically increasing or decreasing)  vari-
       able.  Equidistant or arbitrary sampling can be selected. All columns are resampled based on the new sampling interval.	Several interpola-
       tion schemes are available.

       infile This is a multi-column ASCII [of binary, see -b] file with one column containing the independent variable (which must  be  monotoni-
	      cally  in/de-creasing)  and  the	remaining columns holding misc. data values.  If no file is provided, sample1d reads from standard
	      input.

OPTIONS

       No space between the option flag and the associated arguments.

       -F     Choose from l (Linear), a (Akima spline), and c (natural cubic spline) [Default is -Fa].	You may change	the  default  interpolant;
	      see INTERPOLANT in your .gmtdefaults file.

       -H     Input  file(s) has Header record(s). Number of header records can be changed by editing your .gmtdefaults file. If used, GMT default
	      is 1 header record.

       -I     xinc defines the sampling interval. [Default is the separation between the first and second abcissa point in the infile]

       -M     Multiple segment file. Segments are separated by a record whose first character is flag.	[Default is '>'].

       -N     knotfile is an optional ASCII file with the x locations where the data set will be resampled in the first column

       -S     For equidistant sampling, xstart indicates the location of the first output value. [Default is the smallest even	multiple  of  xinc
	      inside the range of infile]

       -T     Sets the column number of the independent variable [Default is 0 (first)].

       -V     Selects verbose mode, which will send progress reports to stderr [Default runs "silently"].

       -bi    Selects  binary input. Append s for single precision [Default is double].  Append n for the number of columns in the binary file(s).
	      [Default is 2 (or at least the number of columns implied by -T].

       -bo    Selects binary output. Append s for single precision [Default is double].

EXAMPLES

       To resample the file profiles.tdgmb, which contains (time,distance,gravity,magnetics,bathymetry)  records,  at  1km  equidistant  intervals
       using Akima's spline, try'

       sample1d profiles.tdgmb -I1 -Fa -T1 > profiles_equi_d.tdgmb

       To resample the file depths.dt at positions listed in the file grav_pos.dg, using a cubic spline for the interpolation, try

       sample1d depths.dt -Ngrav_pos.dg -Fc > new_depths.dt

SEE ALSO

       gmt(1gmt), filter1d(1gmt)

								    1 Jan 2004							       SAMPLE1D(l)