graph_op_enum

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C++ AD Graph Operator Enum Type

Unary

The unary operators have one argument and one result node. The argument is a node index and the result is the next node.

Binary

The binary operators have two arguments and one result node. The arguments are node indices and the result is the next node. The first (second) argument is the left (right) operand node index.

Conditional Expression

The conditional expression operators have four arguments and one result node. The arguments are node indices and the result is the next node. The first argument is left , the second is right , the third is if_true , the fourth is if_false , the result is given by

      if ( left cop right )
            result = if_true ;
      else
            result = if_false ;

where cop is given in the comment after the enum type values below.

Other Comparisons

Note that

CondExpGt ( left , right , if_true , if_false )

is equivalent to

CondExpLe ( left , right , if_false , if_true )

Similar conversions can be used for all the possible conditional expressions .

Comparison

The comparison operators have two arguments and no result node. The first (second) argument is the left (right) operand node index. The comparison result was true for the value of the independent dynamic parameters and independent variables at which this graph was created.

Other Comparisons

The comparison result true for left > right is equivalent to the comparison result true for right < left . The comparison result false for left > right is equivalent to the comparison result true for left <= right . In a similar fashion, all the possible comparisons results can be converted to a true result for one of the comparisons above.

Summation

The summation operator has one node result and a variable number of arguments. The first argument is the number of nodes in the summation, and the other arguments are the indices of the nodes to be summed. The total number of arguments for this operator is one plus the number of nodes in the summation.

Discrete Function

The discrete function operator has two arguments and one node result. The first argument is the index in discrete_name_vec for the name of the discrete function that is called. The second argument is the index of the node that is the argument to the discrete function.

Atomic Function

The atomic function operator has a variable number of arguments and a variable number of result nodes. There are three extra arguments for atomic_three functions and four extra arguments for atomic_four functions. The total number of operator arguments is the number of extra arguments plus the number of arguments for the function being called. The extra arguments come before the function arguments.

  1. The first operator argument is function name represented by it’s index in the atomic_name_vec .

  2. If this is an atomic four function call, the second operator argument is the call_id .

  3. In the atomic three (atomic four) case, second (third) operator argument is the number of results for this function call. The order of the function results is determined by the function being called.

  4. In the atomic three (atomic four) case, the third (fourth) operator argument is the number of arguments for this function call.

  5. The rest of the operator arguments are the node indices for each of the function arguments. The order of the function arguments is determined by function being called.

Print

The print operator has four arguments.

  1. The first argument is the index in print_text_vec for the before text for this print operator.

  2. The second argument is the index in print_text_vec for the after text for this print operator.

  3. The third argument is the node corresponding to notpos for this print operator.

  4. The fourth argument is the node corresponding to value for this print operator.

Missing Operators

As of yet the following ADFun operators do not have a corresponding graph operator:

  1. Operators to load and store VecAD elements.

  2. An operator for the atomic_two interface.

Enum Values

namespace CppAD { namespace graph {
   enum graph_op_enum {
      abs_graph_op,      // unary: absolute value
      acos_graph_op,     // unary: inverse cosine
      acosh_graph_op,    // unary: inverse hyperbolic cosine
      add_graph_op,      // binary: addition
      asin_graph_op,     // unary: inverse sine
      asinh_graph_op,    // unary: inverse hyperbolic sine
      atan_graph_op,     // unary: inverse tangent
      atanh_graph_op,    // unary: inverse hyperbolic tangent
      atom4_graph_op,    // atomic four function call
      atom_graph_op,     // atomic three function call
      azmul_graph_op,    // binary: absolute zero multiplication
      cexp_eq_graph_op,  // conditional expression: ==
      cexp_le_graph_op,  // conditional expression: <=
      cexp_lt_graph_op,  // conditional expression: <
      comp_eq_graph_op,  // comparison: ==
      comp_le_graph_op,  // comparison: <=
      comp_lt_graph_op,  // comparison: <
      comp_ne_graph_op,  // comparison: !=
      cos_graph_op,      // unary: cosine
      cosh_graph_op,     // unary: hyperbolic cosine
      discrete_graph_op, // discrete function
      div_graph_op,      // binary: division
      erf_graph_op,      // unary: error function
      erfc_graph_op,     // unary: complementary error function
      exp_graph_op,      // unary: exponential
      expm1_graph_op,    // unary: exponential minus one
      log1p_graph_op,    // unary: logarithm of one plus argument
      log_graph_op,      // unary: logarithm
      mul_graph_op,      // binary: multiplication
      neg_graph_op,      // unary: minus
      pow_graph_op,      // binary: first argument raised to second argument
      print_graph_op,    // print during zero order forward
      sign_graph_op,     // unary: sign of argument
      sin_graph_op,      // unary: sine
      sinh_graph_op,     // unary: hyperbolic sine
      sqrt_graph_op,     // unary: square root
      sub_graph_op,      // binary: subtraction
      sum_graph_op,      // summation
      tan_graph_op,      // unary: tangent
      tanh_graph_op,     // unary: hyperbolic tangent
      n_graph_op         // number of graph_op_enum operators
   };
} }

Examples

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