3.4.1.6 Scoping a Coefficient Scoping is the amount of data that you define that you want to use to determine your result. Scoping allows you to define the entire test data or a segment of the test data based on a Start, Finish, or another coefficient within your results. Scoping is best performed as a post test data analysis feature where you can report results from within all of the raw data acquired for a step from your graph. For example, suppose you create a test setup using a tension to distance step. Your distance limit is 10 inches. Normally, you would report the load at 10 inches using the Load (L) coefficient. During this test, the system acquired all of the time-based raw data for load and distance from the Start Test event to the End Test event (10 inch limit). Suppose you wanted to know the load at 250mS after the start of your test or 5 seconds from the end of the test? Suppose you wanted to know the load values at 2 inch, 4 inch, 6 inch or 8 inch? Suppose you wanted to know the distance at 5 lbf? Scoping can be used to answer each of these questions. When a result or step is collecting data, the data is collected at the start of the result or step until the result’s or step’s conclusion. The data collected during a result or step forms an array of data: load/ stress, distance/strain, and time.
Scoping has three operators that may be used:
Operator Description @ Use the @ sign to request the data at a specific location or reference. + The + sign uses the data AFTER this particular location or anchored reference. - The - sign uses the data BEFORE this particular location or anchored reference. Scope Operators When anchoring is used, you can measure a result using the + (after) or - (before) scoping operator. Anchoring is where you select an existing result on your graph trace for the purposes of measuring from this reference point. For example, you may want to measure the load, stress, distance or strain 100mS after the maximum tensile strength. Using scoping, you would first specify the maximum result using the Min/Max/Avg tool. Next, you would select the Point tool. When the Point tool is launched and the scope handle appears on the graph, you move the scope handle until it anchors to the maximum result. When anchoring occurs, the marker for the anchored result turns yellow in color. Then using the Data Definition menu for the new point target (100mS), you specify that using the + operator with a value of 100ms (0.01 S.s). The new marker for the point is generated and appears on the graph.
Shows the delta between two existing coefficients. This is anchoring to a pair of coefficients.
Use the scope handle to adjust your scope setting by moving up or down on either axis. Or, enter the value in the Scope input field.
The markers are yellow indicating they are anchored markers used to calculate the Delta results.
Shows the scope for the Point at 55N. You want to know the Distance @ 55N.
L2 Plus Scoping Examples Scope on a Point (left) and Scope using two existing Coefficients called anchors (right)
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