20 lines
557 B
Mathematica
20 lines
557 B
Mathematica
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function out = vl_nnabs(x,dzdy)
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%VL_NNABS CNN ABS unit.
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% Y = VL_NNABS(X) computes the absolute value of the data X. X can
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% have an arbitrary size. The abs is defined as follows:
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%
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% ABS(X) = |X|.
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%
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% DZDX = VL_NNABS(X, DZDY) computes the derivative of the
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% block projected onto DZDY. DZDX and DZDY have the same
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% dimensions as X and Y respectively.
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% Note, MATLAB built-in function ABS() and SIGN() are used because their
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% support for gpuArray
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if nargin <= 1 || isempty(dzdy)
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out = abs( x ) ;
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else
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out = dzdy .* sign( x );
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end
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