Welcome to Q-Cogo! Q-Cogo was developed as a free, accessible way of solving land survey computations.
Anyone can use Q-Cogo. It is aimed at land surveying and geomatics engineering students, and others wanting to do surveying computations without expensive coordinate geometry software. Q-Cogo is web-based and does not require installation.
Q-Cogo is easy to use, and provides the practiced user with a faster way of performing calculations. For now, it is exclusively a calculator, but future versions may be capable of producing survey drawings.
For more information, contact us at: .
Q-Cogo v. 1.1 (Beta) – Sept 1, 2009
Overview: Capable of basic plane survey computations, area calculations, and point manipulations. Point import and export possible. Automatic sketches provided for cogo operations.
Future versions of Q-Cogo MAY include: traditional traverse adjustments and least squares adjustments, Helmert's transformation, automatic error propagation, interactive operation sketches, linework, labeling and point-and-click drafting facilities, clothoid and roading calculations, map projections, heighting, and pro-rata operations.
Copyright © 2009 Mark Mason. All rights reserved.
Q-Cogo is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
Q-Cogo is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
For more information, contact us at: .
All Q-Cogo operations have been extensively checked; however, the possibility of error (especially with erroneous input) still exists. Be sure to check that results make sense, and double-check important work.
Please report bugs in detail at: .
Each area in Q-Cogo includes pop-up help topics relevant to that area. Simply click on the nearest "?" icon to learn more about using a specific function. Help on all topics is available in the Help area.
You can save a copy of Q-Cogo to your computer to use when you're not connected to the internet. In most browsers, do this by choosing "File --> Save Page As" or similar, and choosing the file type "Web Page, Complete". Doing this in MS Internet Explorer produces a variety of errors: use Mozilla Firefox instead.
Leaving Q-Cogo or (in some browsers) refreshing the page WILL RESULT IN ALL CURRENT POINTS BEING LOST. Save your points by choosing "Select", then copying the record into a text file. Load the points again later by choosing "Edit", then pasting the contents of your text file into the points record.
The Points Record displays a list of current points. Points are listed from left to right in the following columns:
To sort the points record, click on the desired column header in the points record title.
To load points from a text file, click "edit", then paste the file contents into the text area. Points must be space-separated in PNEZD format with no extra lines or special characters.
To expand the points record, double click inside it. Click outside the record to return to normal size.
To store a point, enter its details as follows, then click "Store". Entering an existing point name will edit that point:
"Pt" and "Desc" may be up to 8 characters. Any spaces will be replaced with underscores ('_'). "Pt" must not include commas (',') asterisks ('*') or dashes ('-').
To delete a point, enter its name, then click "Delete". To delete a list of points, enter the point names separated by commas (','). Two points separated by a dash ('-') indicate a range of points. Entering '*.*' indicates all current points.
The Traverse Record displays a history of all traverses performed, whether a point was stored or not. To see previous traverses, simply scroll through the text box.
To expand the traverse record, double click inside it. Click outside the record to return to normal size.
To solve a traverse without storing a point, choose "Solve". To solve a traverse and store a point, choose "Trav" or "SS". ("Trav" will increment the "From" and "BS" inputs, while "SS" will not.) Entering an existing point name will edit that point.
Traverses can be performed by "Azimuth" (angle clockwise from North) or by "Angle" (angle clockwise from a backsight point). Switch between traverse types by clicking on the title.
Traverses can be performed in 2D (horizontal distance) or 3D (slope distance and zenith angle). Switch between traverse dimensions by clicking on the title. If traversing in 3D, click on the HI and HT titles to edit.
The Inverse Record displays a history of all inverses performed. To see previous inverses, simply scroll through the text box.
To expand the inverse record, double click inside it. Click outside the record to return to normal size.
Inverses can be performed between two points or between a point and a line, the line being defined by two points. Switch between inverse types by clicking on the title.
Inverses can be performed in 3D or, for simplicity, in 2D. Switch between inverse dimensions by clicking on the title.
The Intersect Record displays a history of all intersections performed, whether a point was stored or not. To see previous intersections, simply scroll through the text box.
To expand the intersect record, double click inside it. Click outside the record to return to normal size.
To solve an intersection without storing a point, choose "Solve". To solve an intersection and store a point, choose "Store". Entering an existing point name will edit that point.
Intersections can be performed between any two points with a non-zero horizontal distance between them. The intersection may be "Brg-Brg" (two directions), "Brg-Dist" (a direction and a distance) or "Dist-Dist" (two distances). Switch between intersection types by clicking on the title.
Intersections may only be performed in 2D. Resulting points will be stored with an elevation of zero.
The Transform Record displays a history of all transformations performed (shifts, scales and rotations). To see previous transformations, simply scroll through the text box.
To expand the transform record, double click inside it. Click outside the record to return to normal size.
To transform a list of points, enter the point names separated by commas (','). Two points separated by a dash ('-') indicate a range of points. Entering '*.*' indicates all current points.
Points may be shifted ("+N", "+E", or "+Z"), scaled by a scale factor("SF"), or rotated ("Rot"). At least one transformation parameter must be entered. If scaling or rotating points, an About Point must be entered.
"+N", "+E", "+Z", or "Rot" parameters default to 0 if left blank. "SF" defaults to 1.
The Area Record displays a history of all area calculations performed. To see previous areas, simply scroll through the text box.
To expand the area record, double click inside it. Click outside the record to return to normal size.
To calculate the area bounded by a list of points, enter the point names separated by commas (','). Two points separated by a dash ('-') indicate a range of points. Entering '*.*' indicates all current points, in their current order.
An asterisk ('*') after a point (eg: Pt*) indicates a radial point on a curve with the shorter of two possible arc lengths. An asterisk before a point (eg: *Pt) indicates the longer arc length.
Bounding points and curves may be entered in a clockwise or counter-clockwise manner. The bounding path will automatically close to the first point. The bounding path must not cross itself or use a non-radial point more than once.
Before accepting an area calculation, inspect the sketch of the operation to ensure that your path does not intersect or meet itself, and that any curves deflect in the correct direction.
To change the display precision for a particular value type, simply pick it from the appropriate drop down list. Settings will be reflected immediately in the points record. Other records will reflect the change in the results of the next operation.
Note that changing display precision will not affect stored point precision. Stored points always carry ten decimal places to avoid rounding errors.
To change the current Height of Instrument ("HI") or Height of Target ("HT") settings, simply enter the new values. Note that these values may also be changed in the traverse area.
To get help on a topic, choose the appropriate link from the list. The help content box will scroll to the topic. Scroll through the help content box to browse all help topics.
Each area in Q-Cogo includes pop-up help topics relevant to that area. Simply click on the nearest "?" icon to learn more about using a specific function.
The following is a complete index of technical abbreviations used in Q-Cogo:
BC:Beginning of Curve
EC:End of Curve
HI:Height of Instrument
HT:Height of Target