FuncArg
=======

.. cpp:class:: pandas::FuncArg

   pandas C++ class.

Example
-------

.. code-block:: cpp

   #include <pandas/pandas.h>
   using namespace pandas;

   // Use FuncArg
   FuncArg obj;
   // ... operations ...

Constructors
------------

.. list-table::
   :widths: 55 25 20
   :header-rows: 1

   * - Signature
     - Location
     - Example
   * - ``FuncArg() = default``
     - pd_func_dispatch.h:163
     - 
   * - ``FuncArg(FuncArg&&) noexcept = default``
     - pd_func_dispatch.h:164
     - 
   * - ``FuncArg(const FuncArg&) = delete``
     - pd_func_dispatch.h:166
     - 

Construction
------------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``static FuncArg from_array_like(ArrayLikeHandle h)``
     - static FuncArg
     - pd_func_dispatch.h:214
     - 
   * - ``static FuncArg from_callable_handle(CallableHandle h)``
     - static FuncArg
     - pd_func_dispatch.h:182
     - :ref:`View <example-funcarg-from_callable_handle-0>`
   * - ``static FuncArg from_callable_list(std::vector<FuncSpec> fns)``
     - static FuncArg
     - pd_func_dispatch.h:188
     - 
   * - ``static FuncArg from_dict_spec(std::map<std::string, std::vector<FuncSpec>> d)``
     - static FuncArg
     - pd_func_dispatch.h:194
     - :ref:`View <example-funcarg-from_dict_spec-1>`
   * - ``static FuncArg from_index(std::shared_ptr<IndexBase> ix)``
     - static FuncArg
     - pd_func_dispatch.h:208
     - 
   * - ``static FuncArg from_named_agg_list(std::vector<FuncDispatchNamedAggSpec> v)``
     - static FuncArg
     - pd_func_dispatch.h:200
     - :ref:`View <example-funcarg-from_named_agg_list-2>`
   * - ``static FuncArg from_series(std::shared_ptr<Series<T>> s)``
     - FuncArg
     - pd_func_dispatch.h:207
     - 
   * - ``static FuncArg from_string_list(std::vector<std::string> names)``
     - static FuncArg
     - pd_func_dispatch.h:176
     - :ref:`View <example-funcarg-from_string_list-3>`
   * - ``static FuncArg from_string_name(std::string name)``
     - static FuncArg
     - pd_func_dispatch.h:170
     - :ref:`View <example-funcarg-from_string_name-4>`

Other Methods
-------------

.. list-table::
   :widths: 40 20 15 25
   :header-rows: 1

   * - Signature
     - Return Type
     - Location
     - Example
   * - ``static FuncArg none()``
     - static FuncArg
     - pd_func_dispatch.h:220
     - :ref:`View <example-funcarg-none-5>`


Code Examples
-------------

The following examples are extracted from the test suite.

.. _example-funcarg-from_callable_handle-0:

.. dropdown:: from_callable_handle (pd_test_5_all.cpp:53781)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 53771
      :emphasize-lines: 11

                        << "  actual dtype:   [" << dts[0] << "]\n";
          }
      }
      
      static void f_series_apply_dispatch_502719_case_H1_dispatch_callable_square_int(int& local_fail) {
          std::cout << "-- case_H1_dispatch_callable_square_int\n";
          pandas::Series<std::int64_t> s({2, 3, 4}, "v");
          auto h = dispatch_test_helpers::make_stub_callable(
              dispatch_test_helpers::test_cell_int_cb([](double x) { return static_cast<std::int64_t>(x * x); }),
              "square");
          pandas::Result r = s.apply_dispatch(pandas::FuncArg::from_callable_handle(h));
          bool got = std::holds_alternative<std::unique_ptr<pandas::Series<numpy::float64>>>(r.value);
          pandas_tests::check(got, "case_H1.is_series_float64", local_fail);
          if (!got) return;
          auto& sp = std::get<std::unique_ptr<pandas::Series<numpy::float64>>>(r.value);
          bool ok = (sp->size() == 3) && (*sp)[0] == 4.0 && (*sp)[1] == 9.0 && (*sp)[2] == 16.0;
          pandas_tests::check(ok, "case_H1.values_squared", local_fail);
      }
      
      static void f_series_apply_dispatch_502719_case_H2_dispatch_callable_half_float(int& local_fail) {
          std::cout << "-- case_H2_dispatch_callable_half_float\n";

.. _example-funcarg-from_dict_spec-1:

.. dropdown:: from_dict_spec (pd_test_5_all.cpp:53824)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 53814
      :emphasize-lines: 11

          pandas_tests::check(ok, "case_H3.value_min_1", local_fail);
      }
      
      static void f_series_apply_dispatch_502719_case_H4_funcarg_dict_spec_kind(int& local_fail) {
          std::cout << "-- case_H4_funcarg_dict_spec_kind\n";
          std::map<std::string, std::vector<pandas::FuncSpec>> dict_specs;
          pandas::FuncSpec sum_fs;
          sum_fs.kind = pandas::FuncSpec::Kind::StringName;
          sum_fs.name = "sum";
          dict_specs["v"].push_back(std::move(sum_fs));
          auto fa = pandas::FuncArg::from_dict_spec(std::move(dict_specs));
          pandas_tests::check(fa.kind == pandas::FuncArgKind::DictSpec, "case_H4.dict_spec_kind", local_fail);
          pandas_tests::check(fa.dict_specs.size() == 1, "case_H4.dict_specs_size_1", local_fail);
          pandas_tests::check(fa.dict_specs.at("v").size() == 1, "case_H4.dict_v_size_1", local_fail);
      }
      
      static void f_series_apply_dispatch_502719_case_H5_dispatcher_unknown_throws(int& local_fail) {
          std::cout << "-- case_H5_dispatcher_unknown_throws\n";
          pandas::FuncDispatcher disp;
          pandas::FuncArg fa;
          fa.kind = pandas::FuncArgKind::Unknown;

.. _example-funcarg-from_named_agg_list-2:

.. dropdown:: from_named_agg_list (pd_test_5_all.cpp:110979)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 110969
      :emphasize-lines: 11

          pandas_tests::check(dfp->nrows() == 2, "case_H3.nrows_2", local_fail);
      }
      
      static void f_groupby_agg_dispatch_a91f4c_case_H4_funcarg_named_agg_kind(int& local_fail) {
          std::cout << "-- case_H4_funcarg_named_agg_kind\n";
          pandas::FuncDispatchNamedAggSpec spec;
          spec.out_name = "v_total";
          spec.in_col   = "v";
          spec.fn.kind  = pandas::FuncSpec::Kind::StringName;
          spec.fn.name  = "sum";
          auto fa = pandas::FuncArg::from_named_agg_list({std::move(spec)});
          pandas_tests::check(fa.kind == pandas::FuncArgKind::NamedAggList, "case_H4.kind", local_fail);
          pandas_tests::check(fa.named_aggs.size() == 1, "case_H4.size_1", local_fail);
          pandas_tests::check(fa.named_aggs[0].out_name == "v_total", "case_H4.out_name", local_fail);
          pandas_tests::check(fa.named_aggs[0].in_col == "v", "case_H4.in_col", local_fail);
      }
      
      static void f_groupby_agg_dispatch_a91f4c_case_H5_dfgb_agg_funcarg_named(int& local_fail) {
          std::cout << "-- case_H5_dfgb_agg_funcarg_named\n";
          pandas::DataFrame df_in = make_simple_strkey_float_df();
          auto gb = df_in.groupby("k");

.. _example-funcarg-from_string_list-3:

.. dropdown:: from_string_list (pd_test_5_all.cpp:110964)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 110954
      :emphasize-lines: 11

          pandas_tests::check(got, "case_H2.is_dataframe", local_fail);
          if (!got) return;
          auto& dfp = std::get<std::unique_ptr<pandas::DataFrame>>(r.value);
          pandas_tests::check(dfp->nrows() == 2, "case_H2.nrows_2", local_fail);
      }
      
      static void f_groupby_agg_dispatch_a91f4c_case_H3_dfgb_agg_funcarg_string_list(int& local_fail) {
          std::cout << "-- case_H3_dfgb_agg_funcarg_string_list\n";
          pandas::DataFrame df_in = make_simple_strkey_float_df();
          auto gb = df_in.groupby("k");
          pandas::Result r = gb.agg(pandas::FuncArg::from_string_list({"sum", "mean"}));
          bool got = std::holds_alternative<std::unique_ptr<pandas::DataFrame>>(r.value);
          pandas_tests::check(got, "case_H3.is_dataframe", local_fail);
          if (!got) return;
          auto& dfp = std::get<std::unique_ptr<pandas::DataFrame>>(r.value);
          pandas_tests::check(dfp->nrows() == 2, "case_H3.nrows_2", local_fail);
      }
      
      static void f_groupby_agg_dispatch_a91f4c_case_H4_funcarg_named_agg_kind(int& local_fail) {
          std::cout << "-- case_H4_funcarg_named_agg_kind\n";
          pandas::FuncDispatchNamedAggSpec spec;

.. _example-funcarg-from_string_name-4:

.. dropdown:: from_string_name (pd_test_5_all.cpp:53808)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 53798
      :emphasize-lines: 11

          pandas_tests::check(got, "case_H2.is_series_float64", local_fail);
          if (!got) return;
          auto& sp = std::get<std::unique_ptr<pandas::Series<numpy::float64>>>(r.value);
          bool ok = (sp->size() == 3) && (*sp)[0] == 2.0 && (*sp)[1] == 4.0 && (*sp)[2] == 8.0;
          pandas_tests::check(ok, "case_H2.values_halved", local_fail);
      }
      
      static void f_series_apply_dispatch_502719_case_H3_dispatch_string_name_min(int& local_fail) {
          std::cout << "-- case_H3_dispatch_string_name_min\n";
          pandas::Series<numpy::float64> s({3.0, 1.0, 5.0}, "v");
          pandas::Result r = s.apply_dispatch(pandas::FuncArg::from_string_name("min"));
          bool got = std::holds_alternative<std::unique_ptr<pandas::Series<numpy::float64>>>(r.value);
          pandas_tests::check(got, "case_H3.is_series_float64", local_fail);
          if (!got) return;
          auto& sp = std::get<std::unique_ptr<pandas::Series<numpy::float64>>>(r.value);
          bool ok = (sp->size() == 1) && (*sp)[0] == 1.0;
          pandas_tests::check(ok, "case_H3.value_min_1", local_fail);
      }
      
      static void f_series_apply_dispatch_502719_case_H4_funcarg_dict_spec_kind(int& local_fail) {
          std::cout << "-- case_H4_funcarg_dict_spec_kind\n";

.. _example-funcarg-none-5:

.. dropdown:: none (pd_test_5_all.cpp:90413)
   :class-title: example-dropdown

   .. code-block:: cpp
      :linenos:
      :lineno-start: 90403
      :emphasize-lines: 11

                                          pandas::FillValue::of_bool(true));
              (void)r;
          }, local_fail);
      }
      
      static void f_20_847312_dispatch_complex_none(int& local_fail) {
          std::cout << "-- f_20_847312_dispatch_complex_none\n";
          expect_value_error_duplicate("c12_dispatch_complex_none", [] {
              auto s = make_series<cplx>({{1, 2}, {3, 4}, {5, 6}}, {"c1", "c1", "c2"});
              auto r = s.reindex_dispatch({"c1", "c2", "c3"}, "",
                                          pandas::FillValue::none());
              (void)r;
          }, local_fail);
      }
      
      static void f_20_847313_df_dup_rows_axis0(int& local_fail) {
          std::cout << "-- f_20_847313_df_dup_rows_axis0\n";
          expect_value_error_duplicate("c13_df_dup_rows_axis0", [] {
              std::vector<pandas::Series<std::int64_t>> cols;
              cols.emplace_back(std::vector<std::int64_t>{10, 20, 30});
              cols.emplace_back(std::vector<std::int64_t>{40, 50, 60});