Entering Stadia

TPC can uses stadia along, with a direction value, to compute the coordinates and elevation of a point. You can enter both the upper and lower stadia values or just the difference.

Entering Upper and Lower Values

If you plan on entering both the upper and lower stadia values, include the letters K=Stadia and k=Stadia Bottom Line in the Traverse View format dialog. Enter the upper stadia value in the 'Stadia' column and enter the lower stadia value in the 'StadiaBtm' column. TPC will compute the stadia value internally and use it in the computations.

When you enter both the upper and lower stadia values, TPC also computes the target height by averaging the stadia readings and displays this value in the 'HT' column.

Enter the Stadia Difference

If you normally read just the top or bottom stadia value (1/2 stadia) you may want to enter just the stadia difference as your data. To do this, include the letter K=Stadia in the Traverse View format dialog but not k=Stadia Bottom Line. Then enter the stadia difference in the 'Stadia' column.

Vertical Angles

The equations used to compute stadia allow for vertical angles other than horizontal. However, if you do not enter a vertical angle, the program assumes the reading is horizontal.

Changing the Stadia Constant

To change the stadia constant used by the program, choose Tools | Program Settings, Units. Enter the appropriate Stadia Factor (default=100). The stadia value (difference between the upper and lower stadia lines) is multiplied by this factor to compute the horizontal distance.

Stadia Equation

TPC uses the following equation for stadia.

Horizontal distance = stadia constant * stadia * cos2vertical angle

Vertical distance = stadia constant / 2 * stadia * sin(2*vertical angle)

Where: stadia is the difference between the upper and lower stadia values

This equation allows the stadia to be used at vertical angles other than horizontal.

Related Topics

Traverse View
Entering Traverse Data
Carrying Elevations in a Traverse

Editions

Personal, Premium, Professional