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CLsqFit:GetPtWt
The GetPtWt method returns the weight assigned to an existing sample point.
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nWt = CLsqFit:GetPtWt( nIndex, nChannel* ) nWt1, nWt2, nWt3, nWt4 = CLsqFit:GetPtWt( nIndex ) |
The GetPtWt method uses the index of the target point. The index must either be known from the order that points were added to the sample, or determined by matching the target point's values using FindPt or a more complicated procedure involving GetResid or other method.
Two forms are provided with a different number of return values. If the point uses single-channel data (i.e., typical numeric data) or you specify the channel, then a single weight is returned. If the point involves multi-channel data, up to 4 values will be returned. The number of values returned is determined by the SetNumChannels method. The status can be modified using SetPtWt.
The following example illustrates how to change the weight of an existing point. In this case, the target point's index is found by matching its values:
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L = CLsqFit:new() |
-- create a CLsqFit object |
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L:SetNumCoefs( 2 ) |
-- set 2 coefficients to fit a line |
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-- add a point for x = 3.5, y = 5.15, weight = 1 |
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-- add more points |
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L:Fit() |
-- Fit the line |
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-- do something with the fit results |
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n = L:FindPt( 3.5, 5.15 ) |
-- find the point (if we don't know it has index 1) |
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-- if the point has weight > 5 |
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-- reduce the weight of the point to 2.5 |
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end |
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L:Fit() |
-- get a new fit result using different weights |