CLI reference: lsdtt-linear-stats

Samples a raster along each line feature in a vector file and writes descriptive statistics of the sampled values for every line. Points are taken every interpolating_step_length metres along each line; samples that fall outside the raster are skipped, and a line wholly outside it gets no statistics.

Usage

lsdtt-linear-stats  <path> <parameter_file>
lsdtt-linear-stats  <parameter_file>        # path defaults to ./
lsdtt-linear-stats  -h                      # print help and exit
lsdtt-linear-stats  -v                      # print version and exit
lsdtt-linear-stats  -c                      # print citation and exit

Parameter file format

# Lines beginning with # are comments.
key: value

Keys use snake_case. All keys and their defaults are listed under Parameters below.

---

Multipart lines

vector_fname accepts multipart geometry (MultiLineString and friends). Each feature is split into its parts on read, with the attributes copied onto each, and the split is reported in the log.

Shapefiles are the commonest source of multipart data, and versions before August 2026 discarded it silently — see Vector data.

Example

read_path: /home/alice/data/
read_fname: my_dem.tif
vector_fname: /home/alice/data/faults.fgb
interpolating_step_length: 5

vector_fname is opened as given, not relative to read_path, so give the full path (or a path relative to the directory you run the tool from). Only the first layer of the vector file is read, and the lines must be in the raster's projected CRS; they are not reprojected. The raster must be in a projected CRS with metre units.

Output

<write_fname>_linear_stats.fgb (or .gpkg with write_vector_format: gpkg): the input lines (lines wholly outside the raster are left out), each with these attributes of the raster values sampled along it. The input file's own attributes are not carried over.

length (m), n_values, min, max, range, sum, mean, median, variance_population, variance_sample, stddev_population, stddev_sample, mean_absolute_deviation (about the mean), median_absolute_deviation (about the median), mad_normal_scaled (the median absolute deviation × 1.4826), q25, q75, iqr.

Parameters

This section is generated from the executable's -h json registry. Do not edit it manually.

Status: experimental. This CLI is not yet fully tested.

File I/O

Parameter	Type	Default	Role	Parent	Description	Guidance
read_path	string	./	io	-	Directory from which input files are read.	Defaults to the directory holding the parameter file.
read_fname	string	-	io	-	Input filename, with or without extension (e.g. my_dem.tif).	Read from read_path. lsdtt3 uses GDAL, so any GDAL-readable raster format works. If empty, defaults to the parameter filename stem.
write_path	string	-	io	-	Directory to which output files are written.	Defaults to read_path when not set.
write_fname	string	-	io	-	Output filename prefix (no path, no extension).	All outputs are named <write_fname>_<descriptor>.<ext>. Defaults to the stem of read_fname when not set.

param

Parameter	Type	Default	Role	Parent	Description	Guidance
vector_fname	string	-	-	-	File name for the dataset containing linear features.	Input
interpolating_step_length	float	1.0	-	-	Stride length for sample points when interpolating along linear features.	Process parameters

Output

Parameter	Type	Default	Role	Parent	Description	Guidance
write_vector_format	string	flatgeobuf	param	-	Format for the output file.	Allowed values: gpkg, flatgeobuf/fgb.