GXTC class

class geosoft.gx.GXTC
The TC object is used in gravitational modelling to create
a terrain correction grid from a topography grid. This is
accomplished with a call first to geosoft.gx.GXTC.grregter(), which determines
the terrain correction from an input topography grid, then
to geosoft.gx.GXTC.grterain(), which calculates the actual corrections at
the input positions.
static create((GXContext)ctx, (GXIMG)arg1, (float)arg2, (float)arg3, (float)arg4, (float)arg5, (float)arg6, (float)arg7, (int)arg8, (float)arg9, (int)arg10) → GXTC:
Creates a Terrain Correction object
Parameters:
  • ctx (geosoft.gx.GXContext) – The GX execution context
  • arg1 (geosoft.gx.GXIMG) – topo (DEM) grid
  • arg2 (float) – elevation unit in 1 metre (i.e. 0.3048 for feet)
  • arg3 (float) – inner distance (in topo grid projection units, default in metres)
  • arg4 (float) – outer distance (in topo grid projection units, default in metres)
  • arg5 (float) – terrain density in g/cc
  • arg6 (float) – water density in g/cc
  • arg7 (float) – water reference elevation (in elevation unit)
  • arg8 (int) – True to calculate an edge correction (compensation)
  • arg9 (float) – average elevation beyond max distance (in elevation unit)
  • arg10 (int) – TC_OPT constants
Returns:

TC Object
Return type:

geosoft.gx.GXTC

New in version 5.0.0.

static create_ex((GXContext)ctx, (GXIMG)arg1, (float)arg2, (float)arg3, (float)arg4, (float)arg5, (float)arg6, (float)arg7, (int)arg8, (float)arg9, (int)arg10, (int)arg11) → GXTC:
Creates a Terrain Correction object  with surveytype
Parameters:
  • ctx (geosoft.gx.GXContext) – The GX execution context
  • arg1 (geosoft.gx.GXIMG) – topo (DEM) grid
  • arg2 (float) – elevation unit in 1 metre (i.e. 0.3048 for feet)
  • arg3 (float) – inner distance (in topo grid projection units, default in metres)
  • arg4 (float) – outer distance (in topo grid projection units, default in metres)
  • arg5 (float) – terrain density in g/cc
  • arg6 (float) – water density in g/cc
  • arg7 (float) – water reference elevation (in elevation unit)
  • arg8 (int) – True to calculate an edge correction (compensation)
  • arg9 (float) – average elevation beyond max distance (in elevation unit)
  • arg10 (int) – TC_OPT constants
  • arg11 (int) – TC_SURVEYTYPE constants
Returns:

TC Object
Return type:

geosoft.gx.GXTC

New in version 6.2.0.

g_gterain((GXVV)arg1, (GXVV)arg2, (GXVV)arg3, (GXVV)arg4, (float)arg5, (float)arg6, (int)arg7) → None:
Calculate GG terrain corrections
Parameters:
  • arg1 (geosoft.gx.GXVV) – input X channel data (in topo grid projection units, default in metres)
  • arg2 (geosoft.gx.GXVV) – input Y channel data (in topo grid projection units, default in metres)
  • arg3 (geosoft.gx.GXVV) – input Elevation channel data (in elevation unit)
  • arg4 (geosoft.gx.GXVV) – output Terrain Corrected channel data
  • arg5 (float) – Terrain density (default 2.67)
  • arg6 (float) – Terrain reference level (default 0.0)
  • arg7 (int) – GG_ELEMENT constants
Returns:

Nothing
Return type:

None

New in version 6.0.0.

grregter((GXIMG)arg1, (GXIMG)arg2) → None:
Create a terrain correction grid for a topo grid.
Parameters:
Returns:

Nothing
Return type:

None

New in version 5.0.0.

grterain((GXVV)arg1, (GXVV)arg2, (GXVV)arg3, (GXVV)arg4, (GXVV)arg5, (GXIMG)arg6, (float)arg7) → None:
Calculate terrain corrections.
Parameters:
  • arg1 (geosoft.gx.GXVV) – input X channel data (in topo grid projection units, default in metres)
  • arg2 (geosoft.gx.GXVV) – input Y channel data (in topo grid projection units, default in metres)
  • arg3 (geosoft.gx.GXVV) – input Elevation channel data (in elevation unit)
  • arg4 (geosoft.gx.GXVV) – input slope channel data
  • arg5 (geosoft.gx.GXVV) – output Terrain Corrected channel data
  • arg6 (geosoft.gx.GXIMG) – Image of input correction grid
  • arg7 (float) – Terrain density (default 2.67)
Returns:

Nothing
Return type:

None

New in version 5.0.0.

grterain2((GXVV)arg1, (GXVV)arg2, (GXVV)arg3, (GXVV)arg4, (GXVV)arg5, (GXVV)arg6, (GXIMG)arg7, (float)arg8) → None:
Calculate terrain corrections (work for marine gravity too).
Parameters:
  • arg1 (geosoft.gx.GXVV) – input X channel data (in topo grid projection units, default in metres)
  • arg2 (geosoft.gx.GXVV) – input Y channel data (in topo grid projection units, default in metres)
  • arg3 (geosoft.gx.GXVV) – input Elevation channel data (in elevation unit)
  • arg4 (geosoft.gx.GXVV) – input slope channel data
  • arg5 (geosoft.gx.GXVV) – input Water depth channel data (in metres)
  • arg6 (geosoft.gx.GXVV) – output Terrain Corrected channel data
  • arg7 (geosoft.gx.GXIMG) – Image of input correction grid
  • arg8 (float) – Terrain density (default 2.67)
Returns:

Nothing
Return type:

None

New in version 6.0.0.

is_null() → bool

Check if the instance of geosoft.gx.GXTC is null (undefined)

Returns:True if this is a null instance of geosoft.gx.GXTC, False otherwise.
Return type:bool`
static null() → GXTC

A null (undefined) instance of geosoft.gx.GXTC

Returns:A null geosoft.gx.GXTC
Return type:geosoft.gx.GXTC

TC_OPT constants

Optimization
gx.TC_OPT_NONE = 0
(slow)    no optimization
gx.TC_OPT_MAX = 1
(faster)  desampling and using qspline (4x4 points) interp
on coarser averaged grid

TC_SURVEYTYPE constants

Survey Type
gx.TC_SURVEYTYPE_GROUND = 0
Ground
gx.TC_SURVEYTYPE_SHIPBORNE = 1
Shipborne
gx.TC_SURVEYTYPE_AIRBORNE = 2
Airborne

GG_ELEMENT constants

GG element
gx.GG_ELEMENT_XX = 0
Gxx
gx.GG_ELEMENT_YY = 1
Gyy
gx.GG_ELEMENT_XY = 2
Gxy
gx.GG_ELEMENT_XZ = 3
Gxz
gx.GG_ELEMENT_YZ = 4
Gyz