Minslopeendindex – MTS Multipurpose Elite User Manual
Page 238
Parameters
y-channel - This argument is the channel that represents the Y-axis for the Least Squares fit. The units
for this channel are normally in Force units but it is not a requirement. The unit class of the min load and
max load arguments must be the same as the unit class for this argument.
x-channel – This argument is the channel that represents the X-axis for the Least Squares fit. The units
for this channel are normally in Strain units but it is not a requirement. The unit class of the % strain point
argument must be the same as the unit class for this argument.
% segment length – This argument, which is a percentage, is multiplied by the value determined as the
endpoint index of the analysis region. This number is not necessarily the total number of points in the
range or in the specimen.
% tolerance – This argument is a comparison factor used to expand the region initially selected by the
algorithm. The initial region identified as having the minimum slope is first determined. The region of data
considered is expanded in small increments while the slope of the new line stays within the tolerance
based on the initial region. A value of 100% will not allow the region to expand. A value of 90% will allow
expansion while the slope of the data region is within 90% of the initially determined region.
min load – The argument is used to determine the start of the analysis region. The unit class of this
argument must be the same one used with the y-channel.
max load – The argument is used to determine the start of the analysis region. The unit class of this
argument must be the same one used with the y-channel.
% strain point – The argument is used to determine the start of the analysis region. The unit class of this
argument must be the same one used with the x-channel.
Note:
For more information about how the analysis region is determined, see
(p. 230).
Unit Class
Integer
MinSlopeEndIndex
The MinSlopeStartIndex and MinSlopeEndIndex functions are used to determine a region of data where
the slope of the line is minimized based on the function arguments. The slope of the line is determined
using a Least Squares Fit on the Y and X channel data.
Returns
The MinSlopeEndIndex function returns the last point of the region. If a valid region cannot be located
given the function arguments, a –1 will be returned as the index.
Syntax
MinSlopeEndIndex (y-channel, x-channel, % segment length, % tolerance, min load, max load,
%strain point)
238 | MTS TestSuite
Working with Variables