HP 50g Software

COGO+ is a completely integrated application combining all the functions of the software to be accessed from a simple and clear graphical user interface. COGO+ is available in three editions: Lite, Standard and Professional. The professional and standard editions are designed for the HP 49g+ and HP 50g calculators while the Lite editon is designed for the HP 48gii calculators as well as various emulators for the HP 49g series.

COGO+ Solutions

Feature Comparisons

Below are brief descriptions of all the functions available in COGO+ Pro. The columns on the right indicate which editions of the software include the function.

COGO Functions Lt Std Pro

Point Traverse

  1. Standard Mode - A complete COGO solution. This command line style of program handles everything from simple direction and distance point creation to all types of intersections to full inversing of points.
  2. Sideshot Mode - A scaled down point creation tool. By specifying a starting point and backsight point, points may be calculated by entering an angle right/left, a distance and optional offset. The point can be stored as a Sideshot or Traverse Point.


  1. Inverse Points - Find the direction, horizontal and slope distances, slope and coordinate differences between two points. Easily convert metric <-> imperial with a single key press, and calculate coordinates of any station and offset between the two points when you provide the station at either point.
  2. Inverse Curve - Find all the curve elements by entering points at the beginning and end of the curve, the radius point and the direction of the curve. Coordinates of any station and offset along the curve can be calculated by providing the station at BC, EC or the PI of the curve.
  3. Inverse Angle - Calculate the turned angle at a station by entering the station, backsight and foresight points. Distances to both backsight and foresight are also calculated.
  4. Inverse Point to Line - Enter 2 points along a baseline and a offset point to calculate the offset distance perpendicular to the line, the distances along the baseline that offset point is perpendicular. Optionally create a point at the perpendicular intersection.
  5. Inverse Point to Curve - Enter beginning of curve and end of curve points, a radius point and a offset point to calculate the offset distance perpendicular to the curve, the distances along the curve that offset point is perpendicular. Optionally create a point at the perpendicular intersection.
  6. Inverse Point to Alignment - Choose a defined alignment and then enter point numbers to inverse that point to the design. Station, offset and cut/fill information is displayed. Only available in COGO+ Pro.


Being-being, bearing-distance, distance-dearing, and distance-distance intersections can be calculated from one input form by specifying the known information. Offsets can be used to create offset intersections, etc.

Area by Points

  1. Calculate the area of a polygon by entering the points along the perimeter. Curved and straight segments can be used.
  2. Plot the area polygon on the screen.
  3. Export a DXF file of the polygon.
  4. Calculate pre-determined areas by sliding bearing and hinge point methods. Only available in COGO+ Pro.

Fit Points

  1. Straight Line - Calculate the least squares line that best fits a series of points (linear regression). The direction (azimuth/bearing) of the line and its standard deviation, the Y-Intercept and its standard deviation, and correlation are calculated. Perpendicular offsets can be viewed for each point and the points can be shifted to fall on the line.
  2. Circular Curve - Calculate the radius and the coordinates of the radius point of the least squares circle that best fits a series of points. When providing points along one or both tangents, the program will also solve the BC and/or EC point coordinates. It is possible to enter a radius for the curve that differs from the best-fit radius and recalculate a new least squares circle with the fixed parameter. Radial offsets can be viewed for each point, and the points can be shifted to fall on the curve.
  3. Double Proportion - Enter the 4 points for the North, East, South and West section corners and the record measurements to the lost section corner to calculate the coordinates as per the Double Proportionate Measurement method (BLM).
  4. Irregular Boundary - A combination of single proportion and compass rule is used to re-establish a lost corner as per the Irregular Boundary Adjustment method (BLM).
  5. Grant Boundary - Calculate the positions of lost angle points as per the Grant Boundary Adjustment method (BLM).
COGO+ Lt Adjustments Menu COGO+ Std Adjustments Menu COGO+ Pro Adjustments Menu
Adjustment Functions Lt Std Pro

Compass Rule

Perform a compass rule adjustment on a series of points in a closed loop or to a fixed point. The precision, perimeter/length and misclose information is calculated. Review pre and post-adjustment course dimensions and optionally adjust the point coordinates.


  1. Rotate Points - Rotate a series of points around a specified base point by a entered or calculated angle.
  2. Mirror Points - Mirror a series of points along a baseline as defined by two points.


  1. Shift by N/E/Z - Shift a series of points by entering northing/easting/elevation shift values.
  2. Shift by Distance and Direction - Shift a series of points by entering distance and direction shift values.
  3. Shift by From and To Points - Shift a series of points by entering two points to shift from/to.
  4. Average Points - Compute the average coordinate values of a series of points.
  5. 3D to Plan - Transform 3D point coordinates to 2D cross section points along a cut line as defined by two points.


Scale a series of points from a base point by specified horizontal and vertical scale factors.


Transform a series of points from one coordinate system to another by matching up control points in both systems. Points may be matched up 2D or 3D and the scale factor may be fixed at 1. The least squares solution computes the origin shift of the transformation, rotation and scale factor parameters, the standard deviation in the northing/easting, the elevation shift and the residuals for each control pair.
Not Included Not Included COGO+ Pro Surveying Menu
Surveying Functions Lt Std Pro

Traverse Plus

Emulates data collected from a total station. Can be used to create coordinates from raw observation files by entering distances (slope or horizontal), angles (horizontal and vertical), and heights (instrument and target).
  1. Setups can be known station point and known backsight point, set arbitrary backsight azimuth from a known station point, or a resection. When more than three points are used in a resection, an iterative least squares adjustment method is used to calculate the best estimates for the station coordinates.
  2. Stakeout and reference line/arc calculations (2D or 3D) can be performed from setup information. Stakeout can be to a alignment station and offset.


Create multiple levelling jobs with fully editable observation data.
  1. Review/Export data in a fieldbook style layout.
  2. Store calculated elevations to points in the COGO+ job database.
  3. Calculate cuts/fills from any station in the Levelling job.
  4. Adjust the level circuit or loop between fixed stations.


Create multiple complex 3D alignments with fully editable segments. The horizontal component of an alignment may include straight, curve, and spiral-curve-spiral segments. Vertical curves and straight grades can be used to define the vertical component, and cross section templates can be defined and assigned to portions of, or the whole alignment.
  1. Solve the 3D coordinates for any station and offset along the alignment once defined.
  2. Create reports of the complete alignment at given station intervals.
  3. Calculate coordinates for the entire alignment or portions of the alignment at a given station interval. Points are automatically stored in the COGO+ job database.

Inaccessible Point

Calculate the 3D coordinates of a point that was sighted from two different setups (horizontal and vertical angles). The 3D coordinates of both setup points and instrument heights of each station are required.

Plot Points

Plot on the screen a range of points, or all the points within the current job. Zoom and pan to get a graphical look at the point relationships within the job.
COGO+ Lt Tools Menu COGO+ Std Tools Menu COGO+ Pro Tools Menu
Tools Lt Std Pro

Triangle Solver

Solve the remaining parts, area and perimeter of any triangle when providing 3 known parts.

Horizontal Curve Solver

The horizontal curve solver solves all the curve parameters when two parameters are provided, with one known parameter being either the radius or deflection angle, or provide the arc length and chord length to solve using Newton's method.
  1. Solve coordinates for any station and offset along the curve when additional information is given (coordinates and direction).
  2. Includes 3-point curve solver.
  3. Solve the radius and coordinates of the radius point of a curve through a fixed point and fixed tangents.
  4. Includes a spiral curve solver with ability to solve coordinates for any station and offset along the SCS transition curve when additional information is given (coordinates and direction).

Vertical Curve Solver

Solve a vertical curve by entering grades or elevations. Fixed point vertical curves and slope intersections are also included.
  1. Solve the elevation at any station on the vertical curve.
  2. Solve the station(s) at a given elevation.
  3. Solve the elevations for all stations at a given interval.

Bearing ←→ Azimuth Conversions

Simple application to easily convert between quadrant bearings and azimuths.

User Settings

Many settings are available for the user to customize the software. Units, input and output preferences, program behaviour, user-defined scale factor, projection zones, user-created codelists and cross section templates are all managed through the user settings option.
COGO+ Lt Data Menu COGO+ Std Data Menu COGO+ Pro Data Menu
Data Functions Lt Std Pro

Job Manager

The job manager displays all the jobs created, allows the user to create new jobs and delete jobs no longer needed as well as backup and restore job to/from the SD card.

Store New Point

Store and edit point coordinates in the current job.

Review Points

  1. View the coordinates of a single point in the job.
  2. View the coordinates of all points in the job or a range of points.
  3. Browse a list of all the points in the job and select a point to view its coordinates.
  4. Scroll through all the point coordinates.
  5. Renumber points by specifying a new starting point number or an additive number.

Delete Points

Delete points from the current job.


  1. Import comma, space or tab delimited ASCII files.
  2. Export comma, space or tab delimited ASCII files, and choose the number of decimals.
  3. Export DXF files of points in the job database to open directly in a CAD program.
  4. Export KML files of points in the job database to view in Google Earth. Only available in COGO+ Pro.
  5. Export Lat/Long delimited ASCII files. Only available in COGO+ Pro.
  6. Import and Export Codelists.
Not Included Not Included COGO+ Pro Geodetic Menu
Geodetic Functions Lt Std Pro


Convert between grid coordinates and geodetic (latitude/longitude) coordinates. Many different projection zones are pre-defined for use, including UTM and all US State Plane zones. Transverse Mercator and Lambert Conformal Conic (both 1SP and 2SP) projections that are currently not pre-defined can be added upon request.
  1. The convergence angle at the point and grid/elevation/combined scale factors are calculated along with the conversion.
  2. Define your own custom projection and custom ellipsoid through the geodetic user settings.
  3. Store solved grid coordinates as points in the COGO+ job database.

Ellipsoid Calculations

DIRECT and INVERSE solutions of geodesics on the ellipsoid using Vincenty's equations. INVERSE calculations can be done from geodetic or grid coordinate input.
Support and Downloads
Buy Now