foxtrot_xray Posted July 17, 2014 Share Posted July 17, 2014 An odd question, but something I've noticed in the datasheets recently. Take for example this sheet (trimmed): JV7206 DESIGNATION - DAVIS JV7206 PID - JV7206 JV7206 STATE/COUNTY- MD/WASHINGTON JV7206 COUNTRY - US JV7206 USGS QUAD - HARPERS FERRY (1988) JV7206 JV7206 *CURRENT SURVEY CONTROL JV7206 ______________________________________________________________________ JV7206* NAD 83(2011) POSITION- 39 22 03.40338(N) 077 40 15.60611(W) ADJUSTED JV7206* NAD 83(2011) ELLIP HT- 136.923 (meters) (06/27/12) ADJUSTED JV7206* NAD 83(2011) EPOCH - 2010.00 JV7206* NAVD 88 ORTHO HEIGHT - 170.3 (meters) 559. (feet) GPS OBS JV7206 ______________________________________________________________________ JV7206 NAVD 88 orthometric height was determined with geoid model GEOID93 JV7206 GEOID HEIGHT - -33.65 (meters) GEOID93 JV7206 GEOID HEIGHT - -33.32 (meters) GEOID12A JV7206 NAD 83(2011) X - 1,054,310.552 (meters) COMP JV7206 NAD 83(2011) Y - -4,823,773.992 (meters) COMP JV7206 NAD 83(2011) Z - 4,024,038.078 (meters) COMP JV7206 LAPLACE CORR - 7.17 (seconds) DEFLEC12A JV7206 JV7206 FGDC Geospatial Positioning Accuracy Standards (95% confidence, cm) JV7206 Type Horiz Ellip Dist(km) JV7206 ------------------------------------------------------------------- JV7206 NETWORK 1.48 1.84 JV7206 ------------------------------------------------------------------- JV7206 MEDIAN LOCAL ACCURACY AND DIST (006 points) 1.48 1.69 6.83 JV7206 ------------------------------------------------------------------- Note that under the Current Survey Control area, there's no mention of a Horizontal Order or a Vertical Order. Does this mean that this station has no order for both those? Seems a little strange considering there's a Network Accuracy section. Could someone tell me if my assumption's correct, or am I missing something? Cheers - Me. Quote Link to comment
+Ernmark Posted July 17, 2014 Share Posted July 17, 2014 (edited) Did you note the link in the line after your trim of the 'sheet: The Local and Network Accuracy Data Sheet Program lna_ret Version 2.5 Date December 3, 2013 National Geodetic Survey, Retrieval Date = JULY 17, 2014 JV7206 ******************************************************************** JV7206 ACCURACIES - Complete network and local accuracy information. JV7206 DESIGNATION - DAVIS JV7206 PID - JV7206 JV7206 JV7206 Note that Horiz and Ellip values are accuracies at 95% confidence per JV7206 the FGDC accuracy standards. The values of SD_N, SD_E and SD_h are the JV7206 standard deviations (one sigma) of the coordinates (NETWORK) or JV7206 of the difference in the coordinates (LOCAL) in Latitude, Longitude JV7206 and Ellipsoid Height. The value CorrNE is the correlation JV7206 coefficient between the latitude and longitude components of either JV7206 the coordinate (NETWORK) or coordinate difference (LOCAL). The Dist JV7206 value is the three-dimensional straight-line slope distance, in km, JV7206 between station JV7206 and the corresponding Local station. Local JV7206 stations include any other station, regardless of distance, that JV7206 has been processed simultaneously with the station, in any project. JV7206 JV7206 Statistical information, in cm, follows. Correlation is unitless. JV7206 JV7206 Type/PID Horiz Ellip Dist(km) SD_N SD_E SD_h CorrNE JV7206 ------------------------------------------------------------------- JV7206 NETWORK 1.48 1.84 0.65 0.55 0.94 -0.03851109 JV7206 ------------------------------------------------------------------- JV7206 LOCAL (006 points): JV7206 JV7254 1.42 1.25 4.23 0.61 0.54 0.64 -0.18168922 JV7206 JV7215 1.48 1.25 5.12 0.64 0.56 0.64 -0.23513394 JV7206 JV7233 1.59 1.57 6.20 0.69 0.60 0.80 -0.08848601 JV7206 JV7242 1.60 2.18 7.47 0.71 0.59 1.11 -0.00521287 JV7206 JV7224 1.48 2.04 7.63 0.67 0.52 1.04 +0.09634709 JV7206 JV7196 1.39 1.80 11.21 0.62 0.50 0.92 +0.05439072 JV7206 JV7206 MEDIAN 1.48 1.69 6.83 JV7206 ------------------------------------------------------------------- ...interesting! Edited July 17, 2014 by Ernmark Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.