SNAP & CONCORD Downloads

SNAP

SNAP (Survey Network Adjustment Package) is a suite of programs for adjusting the coordinates of stations in a survey network to best fit the observed data. It can use GPS data (baselines or multistation vector and point data), horizontal angles, zenith distances, slope and horizontal distances, azimuths, projection bearings, levelled height differences, latitude, longitude, and height observations.

SNAP runs on most recent versions of Microsoft Windows.

From here you can download the SNAP installation file snap_install.msi in a zip file. To install SNAP extract and run the installation file.

Some of the utility programs supplied with SNAP require the perl interpreter to be installed on the computer. This is can be obtained from the Activestate website.

CONCORD

CONCORD is a component of SNAP that converts coordinates between various different coordinates systems such as New Zealand Map Grid coordinates, Meridional Circuit Coordinates and NZGD49 or NZGD2000 latitude and longitude coordinates. CONCORD is an DOS command line program (run from a windows DOS box).

CONCORD that can be downloaded separately from the SNAP suite. To install it extract the contents of the zip file into a folder, and set the PATH environment variable to include that folder.

The source code for concord with build instructions for a linux environment is available at http://github.com/linz/concord.

Downloads

Download and use of these software applications is taken to be acceptance of the following conditions:

1. LINZ does not offer any support for this software.
2. The software is provided "as is" and without warranty of any kind. In no event shall LINZ be liable for loss of any kind whatsoever with respect to the download, installation and use of the software.
3. The software is designed to work with MS Windows. However, LINZ makes no warranty regarding the performance or non-performance of the software on any particular system or system configuration.

Download other geodetic software or check LINZ datasets, downloads and software.

SNAP add on packages

The following add-on packages are available for SNAP. To use a package download and save the ZIP file, then use the snap_manager install function (in the Tools menu) to add them to SNAP.

Program updates

4 October 2010
Adds a new feature to SNAP for reading station information and observation data from CSV (delimited text files) as an alternative to the SNAP format files, as well as several other small enhancements. The listgps program is renamed to snaplist.  For more information review the change log in the help file.

23 August 2010
Minor update to SNAP configuration files relating to orders. Inclusion of the site2gps program into the SNAP package.

24 May 2010
The accuracy specifications for NZGD2000 orders in snap and snapspec configuration files have been updated to implement the LINZS25006 standard for tiers, classes, and orders. Also enhanced SNAP to support additional data types (XYZ point positions, orthometric heights) and angles formatted as decimal degrees.

14 October 2009
Fixes a bug in SNAP causing it to require dates to be supplied for observations even if the adjustment does not include a deformation model.

6 October 2009
The NZGeoid09 geoid model has replaced the previously used unofficial NZGeoid05 model in concord and SNAP. Also a number of functional enhancements to SNAP.

18 March 2009
Fix to snapspec when assigning orders using a posteriori statistics. Update to concord to include Darwin Glacier Lambert Conic coordinate system.

31 July 2008
Update to the import GDB stations function to work with the restructured LINZ website.

29 April 2008
Added listgps program to SNAP distribution, which was previously omitted.

8 February 2008
Removed system limits on the number of stations and parameters in a SNAP adjustment, previously limited to 32,000. Note that SNAP binary files generated used by this version are incompatible with previous versions of SNAP.