In this exercise, you will build a mathematical formula that applies a pay item to a corridor at a specified interval.
In the example used in this exercise, the pay item formula adds recessed pavement markers at 10-foot intervals along the corridor. Similar applications of this formula include lane striping and quantity of posts along a guardrail or fence.
Formulas can also be used to convert pay item quantities from one unit of measure to another. For example, you could create a formula that converts square yards of a given pay item to tonnage.
Pay item formulas, label expressions, and design checks are created in a similar manner. However, unlike label expressions and design checks, pay item formulas are not saved in the current drawing. You will learn how to save and manage pay item formula files in this exercise.
This exercise continues from Exercise 5: Working with Quantity Reports.
Create a pay item formula
This drawing contains a commercial site, which consists of a building footprint, a parking lot, and access roads.
You are notified that pay item formulas must be written to an external file. After the formula file has been saved, it remains associated with the current drawing. Other formulas that you write in the current drawing will be saved to the same formula file.
Save the pay item formula file in the same location as either the drawing with which it is used, or the master pay item list. If you send the drawing to another user, you must also send the formula file.
When you are finished, the formula in the Expression field should look like this:
TRUNC({Item Length}/10)+1
This formula truncates the feature line length to an integer value, and then divides it by ten. The resulting value is used as the pay item count for the recessed pavement marker. If there is a remainder from dividing the feature line length by ten, then one recessed pavement marker is added to the sum.
In the Pay Item List dialog box, in the Pay Item ID number 63407-0000 row, a is displayed in the Formula cell. This indicates that a formula has been added to this pay item.
Generate a detailed quantity takeoff report
Scroll through the report and examine the Recessed Pavement Marker pay items. The alignment is 1090 feet long. The formula you created divided the alignment length by ten, which resulted in the quantity of 110.
Load a different formula file
Use the Open dialog box to navigate to an existing pay item formula file. You can have several formula files available, and switch between them as needed.
To continue this tutorial, go to Exercise 7: Creating a Pay Item List.