updated: 24-Mar-2011

 Copan for Windows

Map Checks

Contents
  1. Check Bearing-Distance Traverses
  2. Map Traverse Data for Checking
  3. Map Traverse Files
  1. Reverse
  2. Notes

Property (lot or parcel) boundaries on many maps, plans/plats or deeds are commonly annotated with azimuths (or bearings), horizontal distances, curve parameters, and areas. Bearing and distance pairs are often known as calls, courses, or metes. Copan refers to sequences of such reduced data as map traverse data and the process of checking the consistency of such data as map check. (Elsewhere, it may be known as closure check, lot check or deed check.)

Use this module to check the closures and areas (where appropriate) of any number of map traverses, including ones with curves, independently of any coordinate file. In fact, Map Check is disabled if a coordfile is open.

Note that if you need to adjust azimuth and distance traverse data or save new points, you should use the § Map Traverses module. Also, this module cannot be used for field data, involving horizontal or vertical circle readings or slope distances. For such needs, use the § Field Data Processing module. Finally, hile there are certain similarities between the Map Check and the Field Data modules, there are various operational differences (other than the type of map/survey data involved). If you are familiar with one and new to the other, please study the appropriate manual and dialog carefully.

1. To Check Bearing-Distance Traverses

From the Calculate menu, choose Check Brng-Dist Traverse (Map Check)

  1. If you have a coordfile open, close it.
  2. Calculate | Check Brng-Dist Traverse (Map Check)...
  3. Optionally Load... a traverse Data file. This may be an older-format loop file or a newer-format map traverse file (see Map Traverse Files below).
  4. Optionally enter conversions: an Azimuth Correction, to be added to every bearing; a Units Factor, for converting distance units to coordinate units; a Scale Factor, for a combined map projection and sea-level (or elevation) factor.
  5. Enter or edit the bearing-distance traverse data in the big edit box. See below for a description of map traverse data for checking.
    To move the text cursor within the big edit box, use the Arrow, Tab, or Enter keys, or the mouse pointer. Do not use the Space key to separate fields. To delete a chunk of text, select it with the mouse then click Cut (or type Ctrl-X) but be careful not to delete the embedded tabs within a line. To manually insert a tab, Copy and Paste an existing one. The Ctrl-Insert and Ctrl-Delete key combinations act like the Ins and Del buttons, that is, they insert and delete a line of data. To add a Point number automatically to the next blank line, press Enter when in the Distance column of the previous line.
  6. Optionally List the map traverse Data.
  7. Save the Data for reuse.
  8. Optionally Reverse the direction of the map traverse Data.
  9. Calculate (or OK) the traverses.
  10. To graphically view the traverses: Close or hide the Info Display window if it is open, and minimize or move aside — but do not close — the Map Check window.

To check map survey data: enter bearings and distances in the big box, and click Calculate.click for larger view

2. Map Traverse Data for Checking

3. Map Traverse Files

A map traverse file, as it is plain text (or Ascii), can have any name, though names with the .mt extension is advisable. You can edit it outside of Copan, but be sure to maintain proper formatting:
Example Map traverse file.
Here's a map traverse file ready to be Loaded for checking.
Map Traverses
1st dummy line
2nd dummy line
3rd dummy line
1.0000000000
1.0000000000
0.0000000000
1                       Parcel B
2   092.2112    160.40
3   182.0352    160.93
4   "           048.32
5   183.4005    059.19
6   260.5657    160.73
7   000.0812    061.41
8   002.1748    077.60
1   002.1748    161.24

4. Reverse

Occasionally, you'd like to use an already entered traverse but in the reverse direction. Use the Reverse button to reverse the current map traverses (from last to first), each one in reverse point order.

Note that reversed traverse data are shown in their combined interpreted and converted form (i.e., after expressions are evaluated and conversions are applied). So if you want only the raw (or unconverted) data reversed, you must first temporarily remove the conversions.

5. Notes

updated: 24-Mar-2011