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e-Data  —  Civilcad Neutral

This option processes Civilcad Neutral files (Civilcad Raw Data Editor format only) derived from data collector or total station data.

The Civilcad Neutral File window is displayed when this format is selected in the e-Data option of the Survey Menu.

If the Civilcad Neutral data contains traverse, network or resection observations as well as radiation observations for detail pickup, the file should first be processed using the All data or Traverse/network modes so that the control stations may be adjusted before processing the radiation observations. As with any of the other similar options that process traverse or network data, the observations detected in the Civilcad Neutral file will be written to an Extract file which may be edited if necessary, before final processing and adjustment (see Extract file for more information). Following computation and adjustment of the traverse/network framework in this manner, the file may then be processed again using the Radiations only mode to compute the radiated points.

Many of the conventions used by Geoida during data processing apply equally to other options as well as to this option. Refer to the section Meaning, sorting and correction of control, traverse and network observations in the Extract file topic for information regarding use of the Mean control observations check-box option.

Refer also to Survey Data Processing for a list of topics with further general information and to Traverse and Network Processing for information specific to the traverse or network data reduction procedure.

Specifics

Geoida recognises all standard neutral file record codes (Civilcad Raw Data Editor only - neutral files written by the older Translate option are not supported). Refer to the Civilcad reference manual for details of the codes. Note that any settings for the CORR (sea-level and curvature/refraction corrections) and SCALE (projection scale factor) records are not used since these are incorporated into the processing according to job and option settings.

When processing using the All data or Traverse/network modes, Geoida searches for either raw observations or sets of reduced observations. If sets of reduced observations can be identified, these will be used for preference. But if the neutral file contains only raw observations, Geoida will analyse the data to attempt to separate single radiated (pickup) observations from control observations, compiling and meaning any repeated observations to the same points and observations on both faces - for this process to be successful, the observations are expected to be in an orderly and logical sequence. For further details of this process, refer to the section Total Station derived data under Survey Options - General Notes.

If the neutral file contains both raw observations and sets of meaned and corrected observations derived from the raw observations, and, according to the instrument type, also preserves a suitable means of identifying the start and end of the sets that Geoida is able to recognise, Geoida will be able to keep the raw and corrected observations separate. For example, the Sokkia SDR20 v3.05+ data collection program inserts the note "The following MCs are derived from set(s) ..." which Geoida recognises.

But if the Neutral file does not have a suitable note recognised by Geoida, the user may edit the neutral file (either in the Civilcad Raw Data Editor or from within Geoida) and manually insert a NOTE record with the value 'SET' immediately before each set so that Geoida can detect it and separate it from the preceding raw observations. A different record type will signal the end of the set, or the user may manually insert another NOTE record with the value 'END SET'. For example,

#VERSION-1.0 NEUTRAL FILE
AMODE     HM=O,     VM=Z
NOTE      TRANSLATOR: SOKSDR vers B.02
NOTE      RAW FILE HEADER INFO: ANG=DECDEG/DIST=M/PT=ENZ
UNIT      UL=M,     UA=D
JOB       961212
SCALE     1.000000
NOTE      COMP BASIN ASCON
NOTE      Sea level crn:N
NOTE      C and R crn : Y
NOTE      Atmos crn : N
NOTE      12-Dec-96 14:34
EDMTYPE   ET= ,     EO=0.000, EP=0.000
STN       ID=4,     HI=      , CO=1522/2
XYZ       ID=4,     E= 422.517, N= 987.569, H=     0.0
SS        ID=3,     HA=  0.0000, VA= 89.9686, SD=        , HT= 0.000, CO=1522/1
SS        ID=2,     HA=260.5419, VA= 90.0119, SD=  78.475, HT= 0.000, CO=7 OS SP
SS        ID=3,     HA=260.5428, VA=270.1458, SD=        , HT= 0.000, CO=1522/1
SS        ID=2,     HA=161.0853, VA=269.9856, SD=  78.475, HT= 0.000, CO=7 OS SP
NOTE      SET
SS        ID=3,     HA=180.3365, VA= 89.9114, SD=        , HT=      , CO=1522/1
SS        ID=2,     HA= 80.8788, VA= 90.0129, SD=  78.475, HT=      , CO=7 OS SP
NOTE      END SET
STN       ID=3,     HI= 1.615, CO=1522/1
XYZ       ID=3,     E= 422.045, N= 907.289, H=  10.265
BKB       ID=4,     AZ=  0.3365, HA=359.9997
SS        ID=4,     HA=359.9997, VA= 90.2211, SD=        , HT= 1.615, CO=1522/2
SS        ID=10,    HA=344.8347, VA= 90.4211, SD=   3.748, HT= 1.615, CO=TOP BANK
SS        ID=11,    HA=103.7264, VA= 90.1994, SD=  25.412, HT= 1.615, CO=TOP BANK
SS        ID=12,    HA=101.6303, VA= 90.2828, SD=  55.310, HT= 1.615, CO=TOP BANK
SS        ID=13,    HA= 92.2786, VA= 89.6008, SD=  69.353, HT= 1.615, CO=TOP BANK

If there are no distinguishing notes inserted, it is likely that observations recorded as a meaned and corrected set will be meaned with the preceding raw observations at the same setup unless steps have been taken to prevent it happening (eg, by deleting or commenting-out all preceding raw observations). The two types of observation are NOT discernible by examination of the neutral file alone but by comparison with the original total station data file from which it was derived. Therefore to process a neutral file without the appropriate notes, the first run should be done with the Mean Control Observations check-box UN-crossed so that the Extract file created may then be edited to delete the raw observations preceding any set where their corrected means are recorded - refer to Editing an Extract file for more information. Then reprocess the Extract file in the Process Extracted Observations option with the Mean Control Observations check-box CROSSED to mean the observations.

Alpha-numeric point IDs - Many instruments and the Civilcad Neutral file translation process support alpha-numeric point IDs. Since Geoida identifies points by number only, a cross-reference may be created whenever a point is read having an alpha-numeric ID. The Alpha-Numeric ID Cross-Reference window is opened where a point number may be entered (for a point not already existing) or selected from a list of existing points - for more information, refer to this topic.

Neutral file from Leica Geo Office - Users of Leica Geo Office wishing to process their field data in Geoida can export the data from Geo Office as a Civilcad Neutral file.

For additional information, see the heading Processing control survey data under the Total Station derived data heading in the Survey Options - General Notes topic.