'read_ncdata': reads variables from netcdf files, recognizing civx data.
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COMBINE ET REMPLACE read_ncfield, read_vel et read_scalar_new
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OUTPUT:
nb_coord,nb_dim,
Civ: =0 or 1, indicates whether the data is civ (A SUPPRIMER ?)
CivStage: =0, ??? A UTILISER POUR REMPLACER civ
=1, civ1 has been performed only
=2, fix1 has been performed
=3, pacth1 has been performed
=4, civ2 has been performed
=5, fix2 has been performed
=6, pacth2 has been performed
time: absolute time
Field
.Txt: (char string) error message if any
.NbDim: number of dimensions (=0 by default)
.NbCoord: number of vector components
.CoordType: expresses the type of coordinate ('px' for image, 'sig' for instruments, or 'phys')
.dt: time interval for the corresponding image pair
.X, .Y, .Z: set of vector coordinates
.U,.V,.W: corresponding set of vector components
.F: warning flags
.FF: false flag, =0 for good vectors
.C: scalar associated with velocity (used for vector colors)
.CoordType
.DijU; matrix of spatial derivatives (DijU(1,1,:)=DUDX,
DijU(1,2,:)=DUDY, Dij(2,1,:)=DVDX, DijU(2,2,:)=DVDY
.A, .AX, .AY: additional scalar
dt:time interval of the image pair red from a single file, or vector with