| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | module athena__activation_linear | ||
| 2 | !! Module containing implementation of the linear activation function | ||
| 3 | !! | ||
| 4 | !! This module implements a scaled linear (affine) activation function. | ||
| 5 | !! | ||
| 6 | !! Mathematical operation: | ||
| 7 | !! \[ f(x) = \alpha x \] | ||
| 8 | !! | ||
| 9 | !! where \(\alpha\) is a scaling factor (typically \(\alpha=1\)) | ||
| 10 | !! | ||
| 11 | !! Derivative: | ||
| 12 | !! \[ f'(x) = \alpha \] | ||
| 13 | !! | ||
| 14 | !! Properties: Linear transformation, no non-linearity introduced | ||
| 15 | !! Used for regression outputs or when no activation is desired | ||
| 16 | use coreutils, only: real32, print_warning | ||
| 17 | use diffstruc, only: array_type, operator(*) | ||
| 18 | use athena__misc_types, only: base_actv_type | ||
| 19 | use athena__misc_types, only: onnx_attribute_type | ||
| 20 | implicit none | ||
| 21 | |||
| 22 | |||
| 23 | private | ||
| 24 | |||
| 25 | public :: linear_actv_type, create_from_onnx_linear_activation | ||
| 26 | |||
| 27 | |||
| 28 | type, extends(base_actv_type) :: linear_actv_type | ||
| 29 | contains | ||
| 30 | procedure, pass(this) :: apply => apply_linear | ||
| 31 | procedure, pass(this) :: reset => reset_linear | ||
| 32 | procedure, pass(this) :: apply_attributes => apply_attributes_linear | ||
| 33 | procedure, pass(this) :: export_attributes => export_attributes_linear | ||
| 34 | end type linear_actv_type | ||
| 35 | |||
| 36 | interface linear_actv_type | ||
| 37 | procedure initialise | ||
| 38 | end interface linear_actv_type | ||
| 39 | |||
| 40 | |||
| 41 | |||
| 42 | contains | ||
| 43 | |||
| 44 | !############################################################################### | ||
| 45 | − | function initialise(scale, attributes) result(activation) | |
| 46 | !! Initialise a linear activation function | ||
| 47 | implicit none | ||
| 48 | |||
| 49 | ! Arguments | ||
| 50 | real(real32), intent(in), optional :: scale | ||
| 51 | !! Optional scale factor for activation output | ||
| 52 | type(onnx_attribute_type), dimension(:), intent(in), optional :: attributes | ||
| 53 | !! Optional array of ONNX attributes | ||
| 54 | type(linear_actv_type) :: activation | ||
| 55 | !! Linear activation type | ||
| 56 | |||
| 57 | |||
| 58 | − | call activation%reset() | |
| 59 | |||
| 60 | − | if(present(scale)) activation%scale = scale | |
| 61 | − | if(abs(activation%scale-1._real32) .gt. 1.e-6_real32)then | |
| 62 | − | activation%apply_scaling = .true. | |
| 63 | end if | ||
| 64 | |||
| 65 | − | if(present(attributes)) then | |
| 66 | − | call activation%apply_attributes(attributes) | |
| 67 | end if | ||
| 68 | |||
| 69 | − | end function initialise | |
| 70 | !------------------------------------------------------------------------------- | ||
| 71 | − | pure subroutine reset_linear(this) | |
| 72 | !! Reset linear activation function attributes and variables | ||
| 73 | implicit none | ||
| 74 | |||
| 75 | ! Arguments | ||
| 76 | class(linear_actv_type), intent(inout) :: this | ||
| 77 | !! Linear activation type | ||
| 78 | |||
| 79 | − | this%name = "linear" | |
| 80 | − | this%scale = 1._real32 | |
| 81 | − | this%threshold = 0._real32 | |
| 82 | − | this%apply_scaling = .false. | |
| 83 | |||
| 84 | − | end subroutine reset_linear | |
| 85 | !------------------------------------------------------------------------------- | ||
| 86 | − | function create_from_onnx_linear_activation(attributes) result(activation) | |
| 87 | !! Create linear activation function from ONNX attributes | ||
| 88 | implicit none | ||
| 89 | |||
| 90 | ! Arguments | ||
| 91 | type(onnx_attribute_type), dimension(:), intent(in) :: attributes | ||
| 92 | !! Array of ONNX attributes | ||
| 93 | |||
| 94 | class(base_actv_type), allocatable :: activation | ||
| 95 | !! Instance of activation type | ||
| 96 | |||
| 97 | − | allocate(activation, source = linear_actv_type(attributes = attributes)) | |
| 98 | |||
| 99 | − | end function create_from_onnx_linear_activation | |
| 100 | !############################################################################### | ||
| 101 | |||
| 102 | |||
| 103 | !############################################################################### | ||
| 104 | − | subroutine apply_attributes_linear(this, attributes) | |
| 105 | !! Load ONNX attributes into linear activation function | ||
| 106 | implicit none | ||
| 107 | |||
| 108 | ! Arguments | ||
| 109 | class(linear_actv_type), intent(inout) :: this | ||
| 110 | !! Linear activation type | ||
| 111 | type(onnx_attribute_type), dimension(:), intent(in) :: attributes | ||
| 112 | !! Array of ONNX attributes | ||
| 113 | |||
| 114 | ! Local variables | ||
| 115 | integer :: i | ||
| 116 | !! Loop variable | ||
| 117 | |||
| 118 | ! Load provided attributes | ||
| 119 | − | do i=1, size(attributes,dim=1) | |
| 120 | − | select case(trim(attributes(i)%name)) | |
| 121 | case("scale") | ||
| 122 | − | read(attributes(i)%val,*) this%scale | |
| 123 | − | if(abs(this%scale-1._real32) .gt. 1.e-6_real32)then | |
| 124 | − | this%apply_scaling = .true. | |
| 125 | else | ||
| 126 | − | this%apply_scaling = .false. | |
| 127 | end if | ||
| 128 | case("name") | ||
| 129 | − | if(trim(attributes(i)%val) .ne. trim(this%name)) then | |
| 130 | call print_warning( & | ||
| 131 | 'Linear activation: name attribute "' // & | ||
| 132 | − | trim(attributes(i)%val) // & | |
| 133 | '"" does not match expected "' // trim(this%name)//'"' & | ||
| 134 | − | ) | |
| 135 | |||
| 136 | end if | ||
| 137 | case default | ||
| 138 | call print_warning( & | ||
| 139 | 'Linear activation: unknown attribute '// & | ||
| 140 | − | trim(attributes(i)%name) & | |
| 141 | − | ) | |
| 142 | end select | ||
| 143 | end do | ||
| 144 | |||
| 145 | − | end subroutine apply_attributes_linear | |
| 146 | !############################################################################### | ||
| 147 | |||
| 148 | |||
| 149 | !############################################################################### | ||
| 150 | − | pure function export_attributes_linear(this) result(attributes) | |
| 151 | !! Export linear activation function attributes as ONNX attributes | ||
| 152 | implicit none | ||
| 153 | |||
| 154 | ! Arguments | ||
| 155 | class(linear_actv_type), intent(in) :: this | ||
| 156 | !! Linear activation type | ||
| 157 | type(onnx_attribute_type), allocatable, dimension(:) :: attributes | ||
| 158 | !! Array of ONNX attributes | ||
| 159 | |||
| 160 | ! Local variables | ||
| 161 | character(50) :: buffer | ||
| 162 | !! Temporary string buffer | ||
| 163 | |||
| 164 | − | allocate(attributes(2)) | |
| 165 | |||
| 166 | − | write(buffer, '(A)') this%name | |
| 167 | − | attributes(1) = onnx_attribute_type( & | |
| 168 | − | "name", "string", trim(adjustl(buffer)) ) | |
| 169 | |||
| 170 | − | write(buffer, '(F10.6)') this%scale | |
| 171 | − | attributes(2) = onnx_attribute_type( & | |
| 172 | − | "scale", "float", trim(adjustl(buffer)) ) | |
| 173 | |||
| 174 | − | end function export_attributes_linear | |
| 175 | !############################################################################### | ||
| 176 | |||
| 177 | |||
| 178 | !############################################################################### | ||
| 179 | − | function apply_linear(this, val) result(output) | |
| 180 | !! Apply linear activation to 1D array | ||
| 181 | !! | ||
| 182 | !! Computes: f = scale * x | ||
| 183 | implicit none | ||
| 184 | |||
| 185 | ! Arguments | ||
| 186 | class(linear_actv_type), intent(in) :: this | ||
| 187 | !! Linear activation type | ||
| 188 | type(array_type), intent(in) :: val | ||
| 189 | !! Input values | ||
| 190 | type(array_type), pointer :: output | ||
| 191 | !! Scaled output values | ||
| 192 | |||
| 193 | − | if(this%apply_scaling)then | |
| 194 | − | output => val * this%scale | |
| 195 | else | ||
| 196 | − | output => val * 1._real32 ! multiplication by 1 to ensure new allocation | |
| 197 | end if | ||
| 198 | − | end function apply_linear | |
| 199 | !############################################################################### | ||
| 200 | |||
| 201 | − | end module athena__activation_linear | |
| 202 |