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extract

Extract wall-normal profiles from a Tecplot FE-quad mesh at user-specified streamwise stations.

Output path, station locations, and wall-normal resolution are read from [extract] in lst.cfg. Freestream metadata is written directly from [flow_conditions] into the HDF5 root attributes.

Options

Option Meaning
INPUT Tecplot FE-quad BLOCK ASCII input file (positional argument)
--cfg, -c Explicit lst.cfg path (auto-discovered when omitted)
--station Streamwise x-coordinate for one profile station (repeatable, overrides lst.cfg)
--surface Surface side to extract from: lower or upper (auto-detected when omitted)

--surface is auto-detected on one-sided meshes and only needs to be set when both surfaces are present.

At least one extraction station is required. Pass one or more --station options, set [extract] stations, or provide the complete x_s, x_e, and d_x range in lst.cfg.

Output goes to extracted_baseflow.hdf5 next to the input file by default. Set hdf5_out, profiles_out, wall_out, n_eta, eta_max, eta_distribution, eta_stretch, and eta_wall_spacing in [extract] when non-default values are needed. The default distribution is tanh with eta_stretch = 2.0. The geometric distribution requires an explicit eta_wall_spacing for the first off-wall interval.

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# minimal — no config required
lst-tools extract mesh.dat --station 0.10 --station 0.20 --station 0.30

# reads stations and output path from lst.cfg
lst-tools extract mesh.dat

# force upper surface on a two-sided mesh
lst-tools extract mesh.dat --station 0.10 --surface upper