sample1d(1gmt) [plan9 man page]
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)
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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)