GXVVU class

class GXVVU(handle=0)

GXVVU class.

These methods are not a class. Utility methods perform various operations on GXVV objects, including pruning, splining, clipping and filtering.

classmethod average_repeat(ref_vv, dat_vv)

Average repeat values.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Repeated values in the reference GXVV will be averaged in the data GXVV. The first value in the data GXVV will be set to the average and subsequent data GXVV values will be dummied out. Data is processed only to the minimum length of the input GXVV lengths.

See also

remove_dummy

classmethod average_repeat2(ref_vv1, ref_vv2, dat_vv)

Average repeat values based on 2 reference channels.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Repeated values in the reference GXVV will be averaged in the data GXVV. The first value in the data GXVV will be set to the average and subsequent data GXVV values will be dummied out. Data is processed only to the minimum length of the input GXVV lengths. Both the reference GXVV values must repeat for the averaging to occur. This version is useful for averaging on repeated (X,Y) locations.

See also

RemoveDummy_VV

classmethod average_repeat2_ex(ref_vv1, ref_vv2, dat_vv, mode)

Average repeat values based on 2 reference channels.

Parameters:

New in version 8.0.1.

License: Geosoft End-User License

Note: Repeated values in the reference GXVV will be set to the mean, median, minimum or maximum value in the data GXVV. The first value in the data GXVV will be reset and subsequent data GXVV values will be dummied out. Data is processed only to the minimum length of the input GXVV lengths. Both the reference GXVV values must repeat for the averaging to occur. This version is useful for averaging on repeated (X,Y) locations.

See also

RemoveDummy_VV

classmethod average_repeat_ex(ref_vv, dat_vv, mode)

Average repeat values.

Parameters:

New in version 8.0.1.

License: Geosoft End-User License

Note: Repeated values in the reference GXVV will be set to the mean, median, minimum or maximum value in the data GXVV. For minimum and maximum, the index in the data GXVV containing the minimum or maximum value is retained, and the other repeated values are dummied out. For mean and median, the first value in the data GXVV will be reset and subsequent data GXVV values will be dummied out. Data is processed only to the minimum length of the input GXVV lengths.

See also

remove_dummy

Search numeric value in a GXVV.

Parameters:
  • val (float) – Value to search for.
  • l_min (int_ref) – Minimum Location
  • l_max (int_ref) – Maximum Location

New in version 7.1.

License: Geosoft End-User License

Note: The GXVV should be sorted.Search comparison is made on double comparison of the data.

classmethod box_cox(vv, lm)

Run Box-Cox (lambda) Transformation on GXVV.

Parameters:
  • vv (GXVV) – [i/o] GXVV
  • lm (float) – [i] Lambda Value

New in version 5.1.8.

License: Geosoft End-User License

classmethod bp_filt(vv_i, vv_o, pr_sw, pr_lw, flen)

Band-pass filter to the specified.

Parameters:
  • vv_i (GXVV) – Input GXVV
  • vv_o (GXVV) – Filtered GXVV
  • pr_sw (float) – Short wavelength cutoff, 0 for highpass
  • pr_lw (float) – Long wavelength cutoff, 0 for lowpass
  • flen (int) – Filter Length, 0 for default length

New in version 5.0.

License: Geosoft End-User License

Note: If the short and long wavelengths are <= 0, the input channel is simply copied to the output channel without filtering.

The wavelengths are in fiducials.

classmethod clip(vv, min, max, clip)

Clip a GXVV to a range.

Parameters:

New in version 5.0.

License: Geosoft Open License

classmethod clip_to_detect_limit(vv, det_limit, conv)

Apply detection limit clipping of data.

Parameters:
  • vv (GXVV) – Input data vv (altered).
  • det_limit (float) – Detection limit
  • conv (int) – Auto-convert negatives?

New in version 5.1.6.

License: Geosoft End-User License

Note: Flow:

  1. If auto-converting negatives, then all negative values
    are replaced by -0.5*value, and detection limit is ignored.
  2. If not auto-converting negatives, and the detection limit is not rDUMMY, then values less than the detection limit are converted to one-half the detection limit.

This function is identical to GXCHIMERA.clip_to_detect_limit.

classmethod close_xy(vv_x, vv_y, x, y)

Find the closest point to an input point (XY).

Parameters:
  • vv_x (GXVV) – X locations
  • vv_y (GXVV) – Y locations
  • x (float) – Input X
  • y (float) – Input Y
Returns:

Index of closest point, -1 if no valid locations, or data is masked.

Return type:

int

New in version 5.1.8.

License: Geosoft End-User License

Note: Input X and Y location VVs, and a location. Returns the index of the point in the GXVV closest to the input point.

classmethod close_xym(vv_x, vv_y, vv_m, x, y)

Find the closest point to an input point, with mask (XY).

Parameters:
  • vv_x (GXVV) – X locations
  • vv_y (GXVV) – Y locations
  • vv_m (GXVV) – Mask values
  • x (float) – Input X
  • y (float) – Input Y
Returns:

Index of closest point, -1 if no valid locations, or data is masked.

Return type:

int

New in version 5.1.8.

License: Geosoft End-User License

Note: Input X and Y location VVs, and a location. Returns the index of the point in the GXVV closest to the input point. This skips points where the mask value is dummy. If no valid points are in the VVs, or all the mask GXVV values are dummy, the returned index is -1.

classmethod close_xyz(vv_x, vv_y, vv_z, x, y, z)

Find the closest point to an input point (XYZ).

Parameters:
  • vv_x (GXVV) – X locations
  • vv_y (GXVV) – Y locations
  • vv_z (GXVV) – Z locations
  • x (float) – Input X
  • y (float) – Input Y
  • z (float) – Input Z
Returns:

Index of closest point, -1 if no valid locations, or data is masked.

Return type:

int

New in version 5.1.8.

License: Geosoft End-User License

Note: Input X, Y and Z location VVs, and a location. Returns the index of the point in the GXVV closest to the input point.

classmethod close_xyzm(vv_x, vv_y, vv_z, vv_m, x, y, z)

Find the closest point to an input point, with mask (XYZ).

Parameters:
  • vv_x (GXVV) – X locations
  • vv_y (GXVV) – Y locations
  • vv_z (GXVV) – Z locations
  • vv_m (GXVV) – Mask values
  • x (float) – Input X
  • y (float) – Input Y
  • z (float) – Input Z
Returns:

Index of closest point, -1 if no valid locations, or data is masked.

Return type:

int

New in version 5.1.8.

License: Geosoft End-User License

Note: Input X, Y and Z location VVs, and a location. Returns the index of the point in the GXVV closest to the input point. This skips points where the mask value is dummy. If no valid points are in the VVs, or all the mask GXVV values are dummy, the returned index is -1.

classmethod decimate(vv, decimate)

Decimate a GXVV.

Parameters:decimate (int) – Decimation factor (must be > 0)

New in version 6.1.

License: Geosoft End-User License

Note: For a decimation factor N, will remove all values except those with indices equal to MN, where M is an integer.

classmethod deviation(vv_x, vv_y, vv_d, x1, y1, x2, y2, line)

Calculate distance of point locations to a straight line

Parameters:
  • vv_x (GXVV) – X GXVV,REAL GXVV
  • vv_y (GXVV) – Y GXVV,REAL GXVV
  • vv_d (GXVV) – Output deviation GXVV,REAL GXVV
  • x1 (float) – X of 1st point to define straight line
  • y1 (float) – Y of 1st point to define straight line
  • x2 (float) – X of 2nd point or line azimuth in degrees (North is 0 degree)
  • y2 (float) – Y of 2nd point or GS_R8DM if line azimuth is defined
  • line (int) – VVU_LINE constants

New in version 5.0.

License: Geosoft End-User License

classmethod distance(vv_x, vv_y, vv_d, x_fid_start, x_fid_incr, y_fid_start, y_fid_incr)

Create a cumulative distance GXVV

Parameters:
  • vv_x (GXVV) – X GXVV,REAL GXVV
  • vv_y (GXVV) – Y GXVV,REAL GXVV
  • vv_d (GXVV) – Output distance GXVV,REAL GXVV
  • x_fid_start (float) – X GXVV fid start
  • x_fid_incr (float) – X GXVV fid incr
  • y_fid_start (float) – Y GXVV fid start
  • y_fid_incr (float) – Y GXVV fid incr

New in version 5.0.

License: Geosoft End-User License

classmethod distance_3d(vv_x, vv_y, vv_z, start_distance, vv_d)

Create a cumulative distance GXVV from X, Y and Z VVs

Parameters:

New in version 8.0.1.

License: Geosoft End-User License

Note: The output GXVV is the length of the shortest X,Y or Z input GXVV. Any values with dummies are ignored - the distance at that point is equal to the distance at the previous valid point. The returned GXVV is the cumulative straight-line distance between the points. No re-sampling is performed. VVs of any type are supported.

classmethod distance_non_cumulative(vv_x, vv_y, vv_d, x_fid_start, x_fid_incr, y_fid_start, y_fid_incr)

Create a non cumulative distance GXVV i.e each distance element is the distance of the corresponding (X,Y) element and the previous element.

Parameters:
  • vv_x (GXVV) – X GXVV,REAL GXVV
  • vv_y (GXVV) – Y GXVV,REAL GXVV
  • vv_d (GXVV) – Output distance GXVV,REAL GXVV
  • x_fid_start (float) – X GXVV fid start
  • x_fid_incr (float) – X GXVV fid incr
  • y_fid_start (float) – Y GXVV fid start
  • y_fid_incr (float) – Y GXVV fid incr

New in version 7.2.

License: Geosoft End-User License

Note: The fist distace element is rDUMMY.

classmethod dummy_back_tracks(vv)

Dummy all points that keep a GXVV from being monotonically increasing.

Parameters:vv (GXVV) – GXVV handle
Returns:The number of items dummied in order to render the GXVV montonically increasing.
Return type:int

New in version 7.0.

License: Geosoft End-User License

Note: The GXVV length remains the same. Any point that is less than or equal to the previous (valid) point in the GXVV is dummied.

classmethod dummy_range(vv, min, max, inside, incl)

Dummy values inside or outside a range in a GXVV

Parameters:
  • vv (GXVV) – GXVV handle
  • min (float) – Minimum range value
  • max (float) – Maximum range value
  • inside (int) – If TRUE, dummy inside the range
  • incl (int) – If TRUE, include Min, Max in the range.

New in version 5.0.

License: Geosoft Open License

Note: If the Inside flag is TRUE, values within the specified range are set to dummy. If the inside flag is FALSE, values outside the range are set to dummy. If the Inclusive flag is TRUE, then dMin and dMax are considered part of the range. If it is FALSE, then < or > are used, and dMin and dMax lie outside the range.

classmethod dummy_range_ex(vv, min, max, inside, include_min, include_max)

Like DummyRangeVVU, with inclusion options for both ends.

Parameters:
  • vv (GXVV) – GXVV handle
  • min (float) – Minimum range value
  • max (float) – Maximum range value
  • inside (int) – If TRUE, dummy inside the range
  • include_min (int) – If TRUE, include Min in the range.
  • include_max (int) – If TRUE, include Max in the range.

New in version 5.0.7.

License: Geosoft Open License

Note: If the Inside flag is TRUE, values within the specified range are set to dummy. If the inside flag is FALSE, values outside the range are set to dummy. If the Inclusive flag is TRUE, then dMin and dMax are considered part of the range. If it is FALSE, then < or > are used, and dMin and dMax lie outside the range.

classmethod dummy_repeat(vv, mode)

Dummy repeat values in a GXVV.

Parameters:mode (int) – VVU_DUMMYREPEAT constants

New in version 5.0.

License: Geosoft End-User License

Note: Either the first, middle or last point will be left.
Use interp to interpolate after if desired.
classmethod dup_stats(data_vv, sample_vv, mean_vv, diff_vv)

Calculate means and differences for duplicate sample pairs

Parameters:
  • data_vv (GXVV) – Duplicate data GXVV
  • sample_vv (GXVV) – Sample Type GXVV
  • mean_vv (GXVV) – Mean values GXVV (returned)
  • diff_vv (GXVV) – Diff values GXVV (returned)

New in version 5.0.

License: Geosoft End-User License

Note: Created for duplicate sample handling in GXCHIMERA. On input, a numeric GXVV containing data values, and a sample type GXVV. Sample pairs have types “1” and “2”. This routine searches for types in order “1 2 1 2”, and writes the mean values of pairs to the mean value GXVV, and the differences with the mean (equal values, negative and positive) to the difference GXVV. Results for samples out of order, for unmatched values, or when the sample type does not equal “1” or “2” are set to dummy.

classmethod exp_dist(vv, seed, mean, length)

Fill with exponentially distributed values.

Parameters:
  • vv (GXVV) – GXVV object
  • seed (int) – Random number generator seed
  • mean (float) – Mean value of distribution (> 0.0)
  • length (int) – Number of values (-1 for all)

New in version 5.1.8.

License: Geosoft End-User License

Note: GXVV is set to input length (except for -1) See RAND for a short discription of the random number generator used.

classmethod filter(vv_i, vv_o, flt)

Apply a convolution filter to a GXVV.

Parameters:

New in version 5.0.

License: Geosoft End-User License

classmethod find_dummy(vv, dir, type, start, end)

Find the first dummy|non-dummy value in GXVV

Parameters:
  • vv (GXVV) – GXVV handle
  • dir (int) – 0 increasing order 1 decreasing order
  • type (int) – 0 to find the first dummy 1 find first non-dummy
  • start (int) – Start search range at element
  • end (int) – End search range at element (-1 for last)
Returns:

The index of the first dummy|non-dummy value in GXVV -1 if not found or if length of GXVV is 0

Return type:

int

New in version 5.0.

License: Geosoft End-User License

Note: Start and end of range are always defined lowest to largest even if decreasing search order. To search entire GXVV range, specify 0,-1.

classmethod find_gaps_3d(vv_x, vv_y, vv_z, gap, vv_g)

Return indices of locations separated from previous locations by more than the input gap distance.

Parameters:
  • vv_x (GXVV) – X GXVV,REAL GXVV
  • vv_y (GXVV) – Y GXVV,REAL GXVV
  • vv_z (GXVV) – Z GXVV,REAL GXVV
  • gap (float) – Gap size (must be greater than zero)
  • vv_g (GXVV) – Returned indices of start of sections after gaps (INT GXVV)

New in version 8.1.

License: Geosoft End-User License

Note: Locate the starting points of line segements determined by an input gap distance. The returned indices indicate where to break the line, given an input gap. The number of returned indices is one less than the number of line segments. (So if there are no gaps the returned GXVV has zero length).

classmethod find_string_items(vv_source, vv_search, pis_source_sorted, pis_search_sorted, pis_case_tolerant, vv_i)

Searches a GXVV for items in a second GXVV, returns indices of those found.

Parameters:
  • vv_source (GXVV) – String GXVV in which to locate items
  • vv_search (GXVV) – String GXVV Items to search for
  • pis_source_sorted (int) – Is the first GXVV already sorted?
  • pis_search_sorted (int) – Is the second GXVV already sorted
  • pis_case_tolerant (int) – Case tolerance for string comparisons
  • vv_i (GXVV) – GS_LONG GXVV of returned indices into the first GXLST.

New in version 7.3.

License: Geosoft End-User License

Note: This is a much more efficient way of determining if items in one GXVV are found in a second, than by searching repeatedly in a loop. The returned GS_LONG GXVV contains the same number of items as the “search items” GXVV, and contains -1 for items where the value is not found, and the index of items that are found. Comparisons are case-tolerant. Non-string VVs are converted to string type VVs (element size 24) internally.

The method requires that the GXVV items be sorted, and will do so internally. Since the input VVs may already be sorted, the method will run faster if this stage can be skipped.

classmethod fractal_filter(vv_i, order, number, vv_o)

Fractal filter a GXVV.

Parameters:
  • vv_i (GXVV) – [i] GXVV
  • order (int) – [i] filter order
  • number (int) – [i] filter number
  • vv_o (GXVV) – [o] filtered GXVV

New in version 6.0.

License: Geosoft End-User License

classmethod interp(vv, input, output)

Replace all dummies by interpolating from valid data.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Edge behaviour
Dummies at the ends are treated as follows for various combinations of the inside and outside interpolation choices:
if ((iOutside==VV_INTERP_EDGE_NEAREST) ||
    (iOutside==VV_INTERP_EDGE_SAME && iInside==VV_INTERP_NEAREST))

     // -- Set dummies to the same value as the last defined element

else if ((iOutside==VV_INTERP_EDGE_LINEAR) ||
         (iOutside==VV_INTERP_EDGE_SAME &&  iInside==VV_INTERP_LINEAR))

     // --- Set dummies using the slope of the last two defined elements

endif

In all other cases and combinations of the two interpolation choices, the dummies are left “as is”.

is_null()

Check if this is a null (undefined) instance

Returns:True if this is a null (undefined) instance, False otherwise.
Return type:bool
classmethod mask(vv_d, vv_m)

Mask dummies in one GXVV onto another.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: GXVV to mask will be resampled to reference GXVV if required. The returned length of the GXVV to mask will be the shorter of the reference GXVV or the mask GXVV.

classmethod mask_and(vv_a, vv_b, vv_c)

Create mask from logical AND of two VVs.

Parameters:

New in version 5.1.8.

License: Geosoft End-User License

Note: If both values are non-dummies, then result is 1, else dummy.

classmethod mask_or(vv_a, vv_b, vv_c)

Create mask from logical OR of two VVs.

Parameters:

New in version 5.1.8.

License: Geosoft End-User License

Note: If either values is non-dummy, then result is 1, else dummy.

classmethod nl_filt(vv_i, vv_o, fwid, pr_ftol)

Applies a non-linear filter.

Parameters:
  • vv_i (GXVV) – Input GXVV
  • vv_o (GXVV) – Filtered GXVV
  • fwid (int) – Filter Width
  • pr_ftol (float) – Filter Tolerance, 0 for 1% of Std. Dev.

New in version 5.0.

License: Geosoft End-User License

classmethod noise_check(vv_i, vv_f, all_tol, num)

Check on deviation of data from variable background in a GXVV

Parameters:
  • vv_i (GXVV) – Input GXVV on which to apply quality control Required in GS_DOUBLE or GS_FLOAT
  • vv_f (GXVV) – Output flag GXVV with result 0 and 1. Required in GS_BYTE
  • all_tol (float) – Allowed deviation over a number of data points in input GXVV (next parameter). Must be >= 0.0
  • num (int) – Number of data points. Must be > 0

New in version 5.0.

License: Geosoft End-User License

Note: This function checks vertical deviation of data in input GXVV against a moving straight line. The straight line at any time is defined by two extreme points of a data segment. Output GXVV will be 0 if data point in input GXVV falls within the deviation, otherwise, it will be 1. Output GXVV will be 0 if the straight line is vertical.

classmethod noise_check2(vv_i, vv_f, vv_d, all_tol, num)

Like noise_check, but returns maximum deviation at all points.

Parameters:
  • vv_i (GXVV) – Input GXVV on which to apply quality control Required in GS_DOUBLE or GS_FLOAT
  • vv_f (GXVV) – Output flag GXVV with result 0 and 1. Required in GS_BYTE
  • vv_d (GXVV) – Output maximum deviation GXVV.
  • all_tol (float) – Allowed deviation over a number of data points in input GXVV (next parameter). Must be >= 0.0
  • num (int) – Number of data points in the line segment. Must be > 0

New in version 6.3.

License: Geosoft End-User License

Note: This function checks vertical deviation of data in an input GXVV against a moving straight line, where the X-axis value is taken to be the data index, and the Y-axis value is the input data GXVV value. The straight line is drawn between data points at the ends of the line segment, whose length is an input.

The output flag GXVV is set to 0 if data point in input GXVV falls within the deviation for all the moving line segments of which it is a part, otherwise, it will be set to 1.

The output maximum deviation GXVV contains the maximum deviation at each point for all the moving line segments that it is a part of.

classmethod normal_dist(vv, seed, mean, var, length)

Fill with normally (Gaussian) distributed values.

Parameters:
  • vv (GXVV) – GXVV object
  • seed (int) – Random number generator seed
  • mean (float) – Mean value of distribution
  • var (float) – Variance of the distribution
  • length (int) – Number of values (-1 for all)

New in version 5.1.8.

License: Geosoft End-User License

Note: GXVV is set to input length (except for -1) See RAND for a short discription of the random number generator used.

classmethod null()

A null (undefined) instance of GXVVU

Returns:A null GXVVU
Return type:GXVVU
classmethod offset_circles(vv_xi, vv_yi, offset, radius, vv_xo, vv_yo)

Get non-overlapping offset location for circular symbols.

Parameters:
  • vv_xi (GXVV) – Input X locations
  • vv_yi (GXVV) – Input Y locations
  • offset (float) – Minimum offset distance
  • radius (float) – Symbol radius
  • vv_xo (GXVV) – Output (offset) X locations
  • vv_yo (GXVV) – Output (offset) Y locations

New in version 5.0.7.

License: Geosoft End-User License

Note: Often on maps plotted symbols and text overlap each other. This routine accepts of GXVV of locations and returns a new set of locations offset from the originals, and guaranteed not to overlap, given the size of the original symbols. The returned offset X, Y locations are offset from the original locations by the minimum of a) the input offset, b) the input symbol radius. This is to ensure that the original location is never covered by the offset symbol.

Care should be taken when choosing the symbol size, because if the point density is too high, all the points will get pushed to the outside edge and your plot will look like a hedgehog (it also takes a lot longer!).

classmethod offset_correct(vv_xi, vv_yi, dist, heading, v_vxo, v_vyo)

Correct locations based on heading and fixed offset.

Parameters:

New in version 5.0.8.

License: Geosoft End-User License

Note: In many applications, measurements are taken with an instrument which is towed behind, or pushed ahead of where the locations are recorded. Use this function to estimate the actual location of the instrument. The method determines the heading along the line, using a “thinned” version of the line. The degree of thinning is based on the size of the offset; the larger the offset, the greater the distance between sample locations used to construct the thinned lined used for determining headings. The thinned line is splined at a frequency greater than the sample frequency, and the heading at any given point is determined from the vector formed by the closest two points on the splined line. The correction (behind, in front, left or right) is determined with respect to the heading, and added to the original location.

IF this method fails, no dummies, no duplicated locations, no reversals are produced.

The algorithm:

  1. Determine average distance between each point = D
  2. Smoothing interval = MAX(2*D, Offset distance) = I
  3. Thin input points to be at least the smoothing interval I apart from each other.
  4. Smoothly re-interpolate the thinned points at five times the original average distance D.
  5. For each input point, calculate the bearing using the nearest points on the smoothed curve
classmethod offset_correct2(vv_xi, vv_yi, dist, azimuth, vv_xo, vv_yo)

Same as offset_correct, but for an arbitrary offset angle.

Parameters:
  • vv_xi (GXVV) – Input X
  • vv_yi (GXVV) – Input Y
  • dist (float) – Offset distance
  • azimuth (float) – Offset azimuth (degrees counter-clockwise from straight ahead)
  • vv_xo (GXVV) – Output X
  • vv_yo (GXVV) – Output Y

New in version 5.1.3.

License: Geosoft End-User License

classmethod offset_correct3(vv_xi, vv_yi, dist, azimuth, interval, vv_xo, vv_yo)

Same as offset_correct2, but specify smoothing interval.

Parameters:
  • vv_xi (GXVV) – Input X
  • vv_yi (GXVV) – Input Y
  • dist (float) – Offset distance
  • azimuth (float) – Offset azimuth (degrees counter-clockwise from straight ahead)
  • interval (float) – Averaging interval - rDUMMY for default
  • vv_xo (GXVV) – Output X
  • vv_yo (GXVV) – Output Y

New in version 5.1.4.

License: Geosoft End-User License

Note: See the algorithm note #2 above for the default smoothing interval.

classmethod offset_correct_xyz(vv_xi, vv_yi, vv_zi, x_off, y_off, z_off, interval, v_vxo, v_vyo, v_vzo)

Correct locations based on heading and fixed offset.

Parameters:
  • vv_xi (GXVV) – Input X
  • vv_yi (GXVV) – Input Y
  • vv_zi (GXVV) – Input Z
  • x_off (float) – Offset along-track (+ve forward)
  • y_off (float) – Offset across-track (+ve to the right)
  • z_off (float) – Vertical Offset (+ve up)
  • interval (float) – Sampling interval - rDUMMY for default
  • v_vxo (GXVV) – Output X
  • v_vyo (GXVV) – Output Y
  • v_vzo (GXVV) – Output Z

New in version 9.0.

License: Geosoft End-User License

Note: In many applications, measurements are taken with an instrument which is towed behind, or pushed ahead of where the locations are recorded. Use this function to estimate the actual location of the instrument. The method determines the heading along the line, using a “thinned” version of the line. The default degree of thinning is based on the size of the offset; the larger the offset, the greater the distance between sample locations used to construct the thinned lined used for determining headings. The thinned line is splined at a frequency greater than the sample frequency, and the heading at any given point is determined from the vector formed by the closest two points on the splined line. The correction (behind, in front, left or right) is determined with respect to the heading, and added to the original location.

IF this method fails, no dummies, no duplicated locations, no reversals are produced.

The algorithm:

  1. Determine average distance between each point = D
  2. Default smoothing interval = MAX(2*D, Offset distance) = I
  3. Thin input points to be at least the smoothing interval I apart from each other.
  4. Smoothly re-interpolate the thinned points at five times the original average distance D.
  5. For each input point, calculate the bearing using the nearest points on the smoothed curve
classmethod offset_rectangles(vv_xi, vv_yi, offset, size_x, size_y, vv_xo, vv_yo)

Get non-overlapping offset location for rectangular symbols.

Parameters:
  • vv_xi (GXVV) – Input X locations
  • vv_yi (GXVV) – Input Y locations
  • offset (float) – Minimum offset distance
  • size_x (float) – Symbol X size (width)
  • size_y (float) – Symbol Y size (height)
  • vv_xo (GXVV) – Output (offset) X locations
  • vv_yo (GXVV) – Output (offset) Y locations

New in version 5.0.7.

License: Geosoft End-User License

Note: Often on maps plotted symbols and text overlap each other. This routine accepts of GXVV of locations and returns a new set of locations offset from the originals, and guaranteed not to overlap, given the size of the original symbols. The returned offset X, Y locations are offset from the original locations by the minimum of a) the input offset, b) the input symbol X or Y size. This is to ensure that the original location is never covered by the offset symbol. In addition, the offset symbol is never place directly below the original location, to make it easier to draw a connecting line.

Care should be taken when choosing the symbol size, because if the point density is too high, all the points will get pushed to the outside edge and your plot will look like a hedgehog (it also takes a lot longer!).

classmethod pick_peak(vv_i, vv_o, pr_tol, width)

Find peaks in a GXVV - method one.

Parameters:
  • vv_i (GXVV) – Input GXVV
  • vv_o (GXVV) – Returned peak GXVV, all dummies except peak points.
  • pr_tol (float) – Minimum value to accept (0.0 to find all)
  • width (int) – Minimum width to accept (1 to find all)

New in version 5.0.

License: Geosoft End-User License

Note: Peaks are the maximum point within a sequence of positive values in the input GXVV. The width is the number of points in the positive sequence.

A GXVV may have to be pre-filtered before finding the peak values:

Use bp_filt to smooth the data as required. Use filter to apply a Laplace filter “-0.5,1.0,-0.5” to make curvature data.

classmethod pick_peak2(vv_i, vv_o, pr_base_lvl, pr_ampl)

Find peaks in a GXVV - method two.

Parameters:
  • vv_i (GXVV) – Input GXVV
  • vv_o (GXVV) – Returned peak GXVV, all dummies except peak points.
  • pr_base_lvl (float) – Base level to accept (0.0 to find all)
  • pr_ampl (float) – Minimum amplitude to accept

New in version 5.0.

License: Geosoft End-User License

Note: Peaks are the maximum point within a sequence of values in the input GXVV. Maximum points must be above the base level and have a local amplitude greater than the minimum amplitude specified.

A GXVV may have to be pre-filtered before finding the peak values.

classmethod pick_peak3(vv_i, vv_x, vv_y, pr_base_lvl, pr_ampl, v_vind, v_vamp, v_vwid, v_vhawid)

Find peaks in a GXVV - method two, returning width and half-amplitude widths.

Parameters:
  • vv_i (GXVV) – [i] data GXVV
  • vv_x (GXVV) – [i] X GXVV used to calculate distance
  • vv_y (GXVV) – [i] Y GXVV used to calculate distance
  • pr_base_lvl (float) – [i] minimum value to accept (0.0 to find all)
  • pr_ampl (float) – [i] amplitude
  • v_vind (GXVV) – [o] Indices with peak locations
  • v_vamp (GXVV) – [o] Amplitudes at the peaks
  • v_vwid (GXVV) – [o] Anomaly widths
  • v_vhawid (GXVV) – [o] Anomaly half-amplitude widths

New in version 6.2.

License: Geosoft End-User License

Note: Uses Method 2 above, but also returns the anomaly width (defined as the distance between the surrounding troughs), and the width at the half-amplitude. The half-amplitude width is calculated in two parts, individually for each side based on the distance from the maximum to the location where the amplitude is mid-way between the maximum and trough.

The returned VVs are packed; no dummies. Instead the indicies of the peak locations are returned.

classmethod poly_fill(vv_d, order, vv_c)

Fill a GXVV with values from an n’th order polynomial, integral x.

Parameters:
  • vv_d (GXVV) – GXVV with output data. (Preset length)
  • order (int) – Order of the polynomial 0-9
  • vv_c (GXVV) – GXVV with polynomial coefficients (input)

New in version 5.0.6.

License: Geosoft End-User License

Note: The output GXVV length must be set as desired before calling.

The X scale is unitless (1 per element), i.e. 0,1,2,3,...

See also

trend, trend2, poly_fill2

classmethod poly_fill2(vv_x, vv_d, order, vv_c)

Fill a GXVV with values from an n’th order polynomial, specified X

Parameters:
  • vv_x (GXVV) – GXVV with x spacing (input)
  • vv_d (GXVV) – GXVV with output data. (Preset length)
  • order (int) – Order of the polynomial 0-9
  • vv_c (GXVV) – GXVV with polynomial coefficients (order+1 values)

New in version 5.0.6.

License: Geosoft End-User License

Note: The output GXVV length must be set as desired before calling. The X scale is defined by a X GXVV (see Trend_VV for unitless X).

See also

trend, trend2, poly_fill

classmethod polygon_mask(vv_x, vv_y, vv_m, pply, mask)

Mask a GXVV using XY data and a polygon.

Parameters:

New in version 6.2.

License: Geosoft End-User License

Note: The VVs have to be the same length

classmethod prune(vv_p, vv_r, o)

Prune values from a GXVV based on reference GXVV

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Pruning will shorten the GXVV by removing values that are either dummy or non-dummy in the reference GXVV

classmethod qc(vv_i, vv_d, v_vf, nominal, max_tol, all_tol, dist, qc)

Quality control on deviation of data from norm in a GXVV

Parameters:
  • vv_i (GXVV) – Input GXVV on which to apply quality control Required in GS_DOUBLE or GS_FLOAT
  • vv_d (GXVV) – Distance GXVV (NULL if criterion #2 does not apply). In GS_DOUBLE or GS_FLOAT
  • v_vf (GXVV) – Output flag GXVV with result 0,1,2,3,-1,-2,-3. Required in GS_BYTE
  • nominal (float) – Nominal reading (required, must not be GS_R8DM)
  • max_tol (float) – Maximum tolerance/deviation applied to a single reading (criterion #1). GS_R8DM if criterion #1 does not apply. Otherwise, must be positive value including 0.0
  • all_tol (float) – Allowed tolerance/deviation over a given distance (next parameter) (criterion #2). GS_R8DM if criterion #2 does not apply. Otherwise, must be positive value including 0.0
  • dist (float) – The specified distance. GS_R8DM if criterion #2 does not apply. Otherwise, must be positive value excluding 0.0
  • qc (int) – QC_CRITERION constants

New in version 5.0.

License: Geosoft End-User License

Note: This function tests data in input GXVV against two separate criteria. Each element of the output GXVV will have one of the following indicators:

Indicator Meaning
0 Input data passed both tests
1 The input data and is greater than the nominal value plus maximum tolerance/deviation (Criterion #1)
2 The input data over a specified distance is greater than the nominal value plus allowed tolerance (Criterion #2)
3 The input data failed on above two tests
-1 The input data and is less than the nominal value minus maximum tolerance (Criterion #1)
-2 The input data over a specified distance is less than the nominal value minus allowed tolerance (Criterion #2)
-3 The input data failed on above two tests
classmethod qc_fill_gaps(vvx, vvy, vvf, vvd, dist)

Calculate fill in line segments

Parameters:
Returns:

1 if error, 0 if successful

Return type:

int

New in version 6.3.

License: Geosoft End-User License

Note: The X & Y VVs are returned as the calculated fill in line segments.

classmethod range_vector_mag(vv1, vv2, min, max)

Find the range of hypotenuse values of two VVs.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: For each value in the VVs, finds sqrt(dV1*dV1 + dV2*dV2) and returns the min and max values.

classmethod regress(vv_x, vv_y, slp, int)

Calculate linear regression through data

Parameters:

New in version 5.0.

License: Geosoft End-User License

classmethod rel_var_dup(data_vv, sample_vv, rel_var, num_dup)

Estimate relative variance of duplicate sample pairs from a database.

Parameters:
  • data_vv (GXVV) – Data GXVV
  • sample_vv (GXVV) – Sample Type GXVV
  • rel_var (float_ref) – Returned relative variance
  • num_dup (int_ref) – Returned number of duplicates used.

New in version 5.0.

License: Geosoft End-User License

Note: Created for duplicate sample handling in GXCHIMERA. On input, a numeric or text GXVV containing data values, and a sample type GXVV. Sample pairs have types “1” and “2”. This routine searches for types in order “1 2 1 2”, and calulates the unnormalized relative variance, defined as the sum of the squared differences between duplicates divided by the sum of the squared mean values of the duplicates. (To get the true rel.var., divide by N-1, where N is the number of duplicate pairs used.) Samples out of order, unmatched pairs, or when the sample type does not equal “1” or “2” are ignored.

classmethod remove_dummy(vv)

Remove dummy values from a GXVV

New in version 5.0.

License: Geosoft Open License

classmethod remove_dummy2(vv1, vv2)

Remove dummy values from 2 VVs.

Parameters:

New in version 5.0.8.

License: Geosoft End-User License

Note: Removes all indices where either GXVV has a dummy, or is not defined (due to length differences).

classmethod remove_dummy3(vv1, vv2, vv3)

Remove dummy values from 3 VVs.

Parameters:

New in version 5.0.8.

License: Geosoft End-User License

Note: Removes all indices where any GXVV has a dummy, or is not defined (due to length differences).

classmethod remove_dummy4(vv1, vv2, vv3, vv4)

Remove dummy values from 4 VVs.

Parameters:

New in version 6.2.

License: Geosoft End-User License

Note: Removes all indices where any GXVV has a dummy, or is not defined (due to length differences).

classmethod remove_dup(data_vv, sample_vv, output)

Remove/average duplicate sample pairs from a database.

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Created for duplicate sample handling in GXCHIMERA. On input, a numeric or text GXVV containing data values, and a sample type GXVV. Sample pairs have types “1” and “2”. This routine searches for types in order “1 2 1 2”, and replaces the pair of values in the data GXVV according to the VV_DUP constants value. Results for samples out of order, for unmatched pairs, or when the sample type does not equal “1” or “2” remain unchanged.

classmethod remove_xy_dup(xvv, yvv, zvv, xy_dup)

Remove/average duplicate samples with the same (X, Y).

Parameters:

New in version 5.0.

License: Geosoft End-User License

Note: Searches for duplicated (X, Y) locations and removes the duplicates (can be more than just a pair). The “Z” values, if defined, are treated according to the value of VV_XYDUP constants. The returned VVs are shortened to the new length, without duplicates. The Z GXVV can be set to NULL on input, in which case it is ignored.

classmethod remove_xy_dup_index(xvv, yvv, index_vv)

Remove duplicate samples with the same (X, Y) and update index.

Parameters:

New in version 7.2.

License: Geosoft End-User License

Note: Searches for duplicated (X, Y) locations and removes the duplicates (can be more than just a pair). The Index GXVV is updated accordingly .i.e if (X,Y) location of Index[0] == Index[1] Index[1] is removed.

classmethod rolling_stats(vv_i, vv_o, stat, window, shrink)

Calculate a statistic in a rolling window.

Parameters:
  • vv_i (GXVV) – Input GXVV
  • vv_o (GXVV) – Output GXVV
  • stat (int) – ST_INFO constants
  • window (int) – Window size (>0, increased to nearest odd value)
  • shrink (int) – Shrink window at ends (1:Yes, 0:No)

New in version 5.1.

License: Geosoft End-User License

Note: If the input VVs are not REAL, copies are made to temporary REALs for processing.

If the window size is even, it is increased by 1 so that the output value is put at the exact center index of the window.

Statistics are calculated on the values in a window surrounding the individual data points.

By shrinking the window at the ends, one-sided effects can be eliminated. For instance, if the data is linear to begin with, a rolling mean will not alter the original data. However, if the window size is kept constant, then values near the ends tend to be pulled up or down.

With shrinking, the window is shrunk so that it always has the same width on both sides of the data point under analysis; at the end points the window width is 1, at the next point in it is 3, and so on, until the full width is reached.

The median value is calculated by sorting the valid data in the window, then selecting the middle value. If the number of valid data points is even, then the average of the two central values is returned.

The mode value is defined as the value which occurs most frequently in the data. This value may not even exist, or may not be unique. In this implementation, the following algorithm is used: The valid data in the window is sorted in ascending order. The number of occurrences of each data value is tracked, and if it occurs more times than any value, it becomes the modal value. If all values are different, this procedure returns the smallest value. If two or more values each have the same (maximum) number of occurrences, then the smallest of these values is returned.

classmethod search_replace(vv, val, rpl)

Search and replace numeric values in a GXVV.

Parameters:
  • val (float) – Value to replace
  • rpl (float) – Replacement

New in version 5.0.

License: Geosoft End-User License

Note: Search comparison is made on double comparison of the data.

See also

SearchReplaceText_VV

classmethod search_replace_text(vv, format, decimal, val, rpl, mode)

Search and replace text values in a GXVV

Parameters:
  • format (int) – String format for numeric GXVV
  • decimal (int) – Decimals for formating numeric GXVV
  • val (str) – Formatted string to replace
  • rpl (str) – Replacement
  • mode (int) – VVU_SRCHREPL_CASE constants

New in version 5.0.

License: Geosoft End-User License

Note: Search comparison is made on string comparison of the data.

See also

SearchReplace_VV

classmethod search_replace_text_ex(vv, format, decimal, val, rpl, mode, items)

Search and replace text values in a GXVV, count items changed.

Parameters:
  • format (int) – String format for numeric GXVV
  • decimal (int) – Decimals for formating numeric GXVV
  • val (str) – Formatted string to replace
  • rpl (str) – Replacement
  • mode (int) – VVU_SRCHREPL_CASE constants
  • items (int_ref) – Number of items replaced (returned)

New in version 6.0.1.

License: Geosoft End-User License

Note: Search comparison is made on a string comparison of the data.

See also

SearchReplaceText_VV

classmethod search_text(vv, text, case, match, start, dir)

Search for a text value in a GXVV

Parameters:
Returns:

Index of first matching text, -1 if not found.

Return type:

int

New in version 5.0.8.

License: Geosoft End-User License

Note: Search comparison is made on string comparison of the data. Returns index of first item matching the input string. If start index is -1 or dummy, then full GXVV is searched. Use VVU_MATCH_INPUT_LENGTH to match the first part of a string. This is also recommended for matching numerical values, since the displayed value in the database may not be the same as the stored value.

See also

sSearchReplace_VV

classmethod spline(vv_x, vv_y, vv_o, length, start, incr, gap, ext, type)

Spline a Y GXVV onto an X GXVV.

Parameters:
  • vv_x (GXVV) – X (no dummies)
  • vv_y (GXVV) – Y to be splined (no dummies)
  • vv_o (GXVV) – Y output
  • length (int) – Output Length
  • start (float) – Starting Location
  • incr (float) – Separation Distance
  • gap (float) – Maximum gap to interpolate across
  • ext (int) – Number of elements to extend
  • type (int) – VVU_SPL constants

New in version 5.0.

License: Geosoft End-User License

classmethod spline2(vv_x, vv_y, vv_x2, vv_o, type)

Spline a Y GXVV onto an X GXVV. Uses specified values of X in X2

Parameters:
  • vv_x (GXVV) – X (no dummies)
  • vv_y (GXVV) – Y to be splined (no dummies)
  • vv_x2 (GXVV) – X2 (no dummies)
  • vv_o (GXVV) – Y output
  • type (int) – VVU_SPL constants

New in version 5.1.3.

License: Geosoft End-User License

classmethod tokenize_to_values(vv, str_val)

Tokenize a string based on any characters.

Parameters:
  • vv (GXVV) – GXVV to place values in
  • str_val (str) – Str - String to parse
Returns:

Number of tokens (length of GXVV)

Return type:

int

New in version 9.0.

License: Geosoft Open License

Note: Parses a series of space, tab or comma-delimited values to a GXVV.

classmethod translate(vv, base, mult)

Translate values in a GXVV

Parameters:
  • base (float) – Base
  • mult (float) – Scale

New in version 5.0.

License: Geosoft Open License

Note: (new GXVV) = ((old GXVV) + base) * scale

classmethod trend(vv_d, order, vv_c)

Calculate an n’th order best-fit polynomial, integral x.

Parameters:
  • vv_d (GXVV) – GXVV with input data
  • order (int) – Order of the polynomial 0-9
  • vv_c (GXVV) – GXVV to hold polynomial coefficients (returned).

New in version 5.0.6.

License: Geosoft End-User License

Note: Returns coefficients c[0] .. c[n]

Y(x) = c[0] + c[1]x + c[2](x**2) + ... + c[n](x**n)

The X scale is unitless (1 per element), i.e. 0,1,2,3,...

The polynomial GXVV length is set to the number of coefficients (order + 1)

classmethod trend2(vv_x, vv_d, order, vv_c)

Calculate an n’th order best-fit polynomial, specified X

Parameters:
  • vv_x (GXVV) – GXVV with x spacing (input)
  • vv_d (GXVV) – GXVV with input data
  • order (int) – Order of the polynomial 0-9
  • vv_c (GXVV) – GXVV to hold polynomial coefficients (returned)

New in version 5.0.6.

License: Geosoft End-User License

Note: Returns coefficients c[0] .. c[n]

Y(x) = c[0] + c[1]x + c[2](x**2) + ... + c[n](x**n)

The X scale is defined by a X GXVV (see Trend_VV for unitless X).

The polynomial GXVV length is set to the number of coefficients (order + 1)

classmethod uniform_dist(vv, seed, min, max, length)

Fill with uniformly distributed values.

Parameters:
  • vv (GXVV) – GXVV object
  • seed (int) – Random number generator seed
  • min (float) – Minimum of range
  • max (float) – Maximum of range
  • length (int) – Number of values (-1 for all)

New in version 5.1.8.

License: Geosoft End-User License

Note: GXVV is set to input length (except for -1) See rand.gxh for a short discription of the random number generator used.

QC_CRITERION constants

Criterion

QC_CRITERION_1

1

gxapi.QC_CRITERION_1 = 0
QC_CRITERION_2

2

gxapi.QC_CRITERION_2 = 1
QC_CRITERION_12

12

gxapi.QC_CRITERION_12 = 2

TEM_ARRAY constants

Array Type

TEM_ARRAY_VERTICALSOUNDING

Verticalsounding

gxapi.TEM_ARRAY_VERTICALSOUNDING = 0
TEM_ARRAY_PROFILING

Profiling

gxapi.TEM_ARRAY_PROFILING = 1
TEM_ARRAY_BOREHOLE

Borehole

gxapi.TEM_ARRAY_BOREHOLE = 2

VV_DUP constants

Duplicate handling mode

VV_DUP_AVERAGE

Average numeric values (for strings, same as VV_DUP_1)

gxapi.VV_DUP_AVERAGE = 0
VV_DUP_1

Use first value of the pair

gxapi.VV_DUP_1 = 1
VV_DUP_2

Use second value of the pair

gxapi.VV_DUP_2 = 2
VV_DUP_DUMMY

Set to dummy

gxapi.VV_DUP_DUMMY = 3
VV_DUP_SAMPLE

Set to “3” (cannot use with string data GXVV)

gxapi.VV_DUP_SAMPLE = 4

VV_XYDUP constants

Sample handling

VV_XYDUP_AVERAGE

Average

gxapi.VV_XYDUP_AVERAGE = 0
VV_XYDUP_SUM

Sum

gxapi.VV_XYDUP_SUM = 1

VVU_CASE constants

String case handling

VVU_CASE_TOLERANT

Tolerant

gxapi.VVU_CASE_TOLERANT = 0
VVU_CASE_SENSITIVE

Sensitive

gxapi.VVU_CASE_SENSITIVE = 1

VVU_CLIP constants

Type of clipping

VVU_CLIP_DUMMY

Clip replaces clipped values with a dummy.

gxapi.VVU_CLIP_DUMMY = 0
VVU_CLIP_LIMIT

Clip replaces clipped values with the limit.

gxapi.VVU_CLIP_LIMIT = 1

VVU_DUMMYREPEAT constants

How to deal with repeats

VVU_DUMMYREPEAT_FIRST

Dummies all but first point.

gxapi.VVU_DUMMYREPEAT_FIRST = 0
VVU_DUMMYREPEAT_LAST

Dummies all but last point.

gxapi.VVU_DUMMYREPEAT_LAST = 1
VVU_DUMMYREPEAT_MIDDLE

Dummies all but middle point.

gxapi.VVU_DUMMYREPEAT_MIDDLE = 2

VVU_INTERP constants

Interpolation method to use

VVU_INTERP_NEAREST

Nearest

gxapi.VVU_INTERP_NEAREST = 1
VVU_INTERP_LINEAR

Linear

gxapi.VVU_INTERP_LINEAR = 2
VVU_INTERP_CUBIC

Cubic

gxapi.VVU_INTERP_CUBIC = 3
VVU_INTERP_AKIMA

Akima

gxapi.VVU_INTERP_AKIMA = 4
VVU_INTERP_PREDICT

Predict

gxapi.VVU_INTERP_PREDICT = 5

VVU_INTERP_EDGE constants

Interpolation method to use on edges

VVU_INTERP_EDGE_NONE

None

gxapi.VVU_INTERP_EDGE_NONE = 0
VVU_INTERP_EDGE_SAME

Same

gxapi.VVU_INTERP_EDGE_SAME = 1
VVU_INTERP_EDGE_NEAREST

Nearest

gxapi.VVU_INTERP_EDGE_NEAREST = 2
VVU_INTERP_EDGE_LINEAR

Linear

gxapi.VVU_INTERP_EDGE_LINEAR = 3

VVU_LINE constants

Line Types

LINE_2_POINTS

Line 2 points

gxapi.LINE_2_POINTS = 0
LINE_POINT_AZIMUTH

Line point azimuth

gxapi.LINE_POINT_AZIMUTH = 1

VVU_MASK constants

Type of clipping

VVU_MASK_INSIDE

Mask GXVV is set to dummy at locations inside the GXPLY.

gxapi.VVU_MASK_INSIDE = 0
VVU_MASK_OUTSIDE

Mask GXVV is set to dummy at locations outside the GXPLY.

gxapi.VVU_MASK_OUTSIDE = 1

VVU_MATCH constants

Matching style

VVU_MATCH_FULL_STRINGS

Entire string

gxapi.VVU_MATCH_FULL_STRINGS = 0
VVU_MATCH_INPUT_LENGTH

Match the first part of a string.

gxapi.VVU_MATCH_INPUT_LENGTH = 1

VVU_MODE constants

Statistic to select

VVU_MODE_MEAN

Mean

gxapi.VVU_MODE_MEAN = 0
VVU_MODE_MEDIAN

Median

gxapi.VVU_MODE_MEDIAN = 1
VVU_MODE_MAXIMUM

Maximum

gxapi.VVU_MODE_MAXIMUM = 2
VVU_MODE_MINIMUM

Minimum

gxapi.VVU_MODE_MINIMUM = 3

VVU_OFFSET constants

Heading

VVU_OFFSET_FORWARD

Forward

gxapi.VVU_OFFSET_FORWARD = 0
VVU_OFFSET_BACKWARD

Backward

gxapi.VVU_OFFSET_BACKWARD = 1
VVU_OFFSET_RIGHT

Right

gxapi.VVU_OFFSET_RIGHT = 2
VVU_OFFSET_LEFT

Left

gxapi.VVU_OFFSET_LEFT = 3

VVU_PRUNE constants

Prune options

VVU_PRUNE_DUMMY

0

gxapi.VVU_PRUNE_DUMMY = 0
VVU_PRUNE_VALID

1

gxapi.VVU_PRUNE_VALID = 1

VVU_SPL constants

Spline types

VVU_SPL_LINEAR

Linear

gxapi.VVU_SPL_LINEAR = 0
VVU_SPL_CUBIC

Cubic

gxapi.VVU_SPL_CUBIC = 1
VVU_SPL_AKIMA

Akima

gxapi.VVU_SPL_AKIMA = 2
VVU_SPL_NEAREST

Nearest

gxapi.VVU_SPL_NEAREST = 3

VVU_SRCHREPL_CASE constants

Search and Replace handling of string case

VVU_SRCHREPL_CASE_TOLERANT

Tolerant

gxapi.VVU_SRCHREPL_CASE_TOLERANT = 0
VVU_SRCHREPL_CASE_SENSITIVE

Sensitive

gxapi.VVU_SRCHREPL_CASE_SENSITIVE = 1