Adds array_to_tuple source/header files

Author: chaburkland

setup.py

@@ -35,6 +35,7 @@ def get_ext_dir(*components: tp.Iterable[str]) -> tp.Sequence[str]:
         sources=[
             'src/_arraykit.c',
             'src/array_go.c',
+            'src/array_to_tuple.c',
             'src/block_index.c',
             'src/delimited_to_arrays.c',
             'src/methods.c',

src/_arraykit.c

@@ -6,6 +6,7 @@
 # include "numpy/arrayobject.h"
 
 # include "array_go.h"
+# include "array_to_tuple.h"
 # include "block_index.h"
 # include "delimited_to_arrays.h"
 # include "methods.h"

src/array_to_tuple.c

@@ -0,0 +1,251 @@
+# include "Python.h"
+
+# define NO_IMPORT_ARRAY
+# define PY_ARRAY_UNIQUE_SYMBOL AK_ARRAY_API
+# define NPY_NO_DEPRECATED_API NPY_1_7_API_VERSION
+
+# include "numpy/arrayobject.h"
+
+# include "array_to_tuple.h"
+# include "utilities.h"
+
+// Given a 1D or 2D array, return a 1D object array of tuples.
+PyObject *
+array_to_tuple_array(PyObject *Py_UNUSED(m), PyObject *a)
+{
+    AK_CHECK_NUMPY_ARRAY(a);
+    PyArrayObject *input_array = (PyArrayObject *)a;
+    int ndim = PyArray_NDIM(input_array);
+    if (ndim != 1 && ndim != 2) {
+        return PyErr_Format(PyExc_NotImplementedError,
+                "Expected 1D or 2D array, not %i.",
+                ndim);
+    }
+
+    npy_intp num_rows = PyArray_DIM(input_array, 0);
+    npy_intp dims[] = {num_rows};
+    // NOTE: this initializes values to NULL, not None
+    PyObject* output = PyArray_SimpleNew(1, dims, NPY_OBJECT);
+    if (output == NULL) {
+        return NULL;
+    }
+
+    PyObject** output_data = (PyObject**)PyArray_DATA((PyArrayObject*)output);
+    PyObject** p = output_data;
+    PyObject** p_end = p + num_rows;
+    npy_intp i = 0;
+    PyObject* tuple;
+    PyObject* item;
+
+    if (ndim == 2) {
+        npy_intp num_cols = PyArray_DIM(input_array, 1);
+        npy_intp j;
+        while (p < p_end) {
+            tuple = PyTuple_New(num_cols);
+            if (tuple == NULL) {
+                goto error;
+            }
+            for (j = 0; j < num_cols; ++j) {
+                // cannot assume input_array is contiguous
+                item = PyArray_ToScalar(PyArray_GETPTR2(input_array, i, j), input_array);
+                if (item == NULL) {
+                    Py_DECREF(tuple);
+                    goto error;
+                }
+                PyTuple_SET_ITEM(tuple, j, item); // steals reference to item
+            }
+            *p++ = tuple; // assign with new ref, no incr needed
+            i++;
+        }
+    }
+    else if (PyArray_TYPE(input_array) != NPY_OBJECT) { // ndim == 1, not object
+        while (p < p_end) {
+            tuple = PyTuple_New(1);
+            if (tuple == NULL) {
+                goto error;
+            }
+            // scalar returned in is native PyObject from object arrays
+            item = PyArray_ToScalar(PyArray_GETPTR1(input_array, i), input_array);
+            if (item == NULL) {
+                Py_DECREF(tuple);
+                goto error;
+            }
+            PyTuple_SET_ITEM(tuple, 0, item); // steals reference to item
+            *p++ = tuple; // assign with new ref, no incr needed
+            i++;
+        }
+    }
+    else { // ndim == 1, object
+        while (p < p_end) {
+            item = *(PyObject**)PyArray_GETPTR1(input_array, i);
+            Py_INCREF(item); // always incref
+            if (PyTuple_Check(item)) {
+                tuple = item; // do not double pack
+            }
+            else {
+                tuple = PyTuple_New(1);
+                if (tuple == NULL) {
+                    goto error;
+                }
+                PyTuple_SET_ITEM(tuple, 0, item); // steals reference to item
+            }
+            *p++ = tuple; // assign with new ref, no incr needed
+            i++;
+        }
+    }
+    PyArray_CLEARFLAGS((PyArrayObject *)output, NPY_ARRAY_WRITEABLE);
+    return output;
+error:
+    p = output_data;
+    p_end = p + num_rows;
+    while (p < p_end) { // decref all tuples within array
+        Py_XDECREF(*p++); // xdec as might be NULL
+    }
+    Py_DECREF(output);
+    return NULL;
+}
+
+//------------------------------------------------------------------------------
+// ArrayToTupleIterator
+
+static PyTypeObject ATTType;
+
+typedef struct ATTObject {
+    PyObject_HEAD
+    PyArrayObject* array;
+    npy_intp num_rows;
+    npy_intp num_cols;
+    Py_ssize_t pos; // current index state, mutated in-place
+} ATTObject;
+
+static inline PyObject *
+ATT_new(PyArrayObject* array,
+        npy_intp num_rows,
+        npy_intp num_cols) {
+    ATTObject* a2dt = PyObject_New(ATTObject, &ATTType);
+    if (!a2dt) {
+        return NULL;
+    }
+    Py_INCREF((PyObject*)array);
+    a2dt->array = array;
+    a2dt->num_rows = num_rows;
+    a2dt->num_cols = num_cols; // -1 for 1D array
+    a2dt->pos = 0;
+    return (PyObject *)a2dt;
+}
+
+static inline void
+ATT_dealloc(ATTObject *self) {
+    Py_DECREF((PyObject*)self->array);
+    PyObject_Del((PyObject*)self);
+}
+
+static inline PyObject*
+ATT_iter(ATTObject *self) {
+    Py_INCREF(self);
+    return (PyObject*)self;
+}
+
+static inline PyObject *
+ATT_iternext(ATTObject *self) {
+    Py_ssize_t i = self->pos;
+    if (i < self->num_rows) {
+        npy_intp num_cols = self->num_cols;
+        PyArrayObject* array = self->array;
+        PyObject* item;
+        PyObject* tuple;
+
+        if (num_cols > -1) { // ndim == 2
+            tuple = PyTuple_New(num_cols);
+            if (tuple == NULL) {
+                return NULL;
+            }
+            for (npy_intp j = 0; j < num_cols; ++j) {
+                // cannot assume array is contiguous
+                item = PyArray_ToScalar(PyArray_GETPTR2(array, i, j), array);
+                if (item == NULL) {
+                    Py_DECREF(tuple);
+                    return NULL;
+                }
+                PyTuple_SET_ITEM(tuple, j, item); // steals ref
+            }
+        }
+        else if (PyArray_TYPE(array) != NPY_OBJECT) { // ndim == 1, not object
+            tuple = PyTuple_New(1);
+            if (tuple == NULL) {
+                return NULL;
+            }
+            item = PyArray_ToScalar(PyArray_GETPTR1(array, i), array);
+            if (item == NULL) {
+                Py_DECREF(tuple);
+                return NULL;
+            }
+            PyTuple_SET_ITEM(tuple, 0, item); // steals ref
+        }
+        else { // ndim == 1, object
+            item = *(PyObject**)PyArray_GETPTR1(array, i);
+            Py_INCREF(item); // always incref
+            if (PyTuple_Check(item)) {
+                tuple = item; // do not double pack
+            }
+            else {
+                tuple = PyTuple_New(1);
+                if (tuple == NULL) {
+                    Py_DECREF(item);
+                    return NULL;
+                }
+                PyTuple_SET_ITEM(tuple, 0, item); // steals ref
+            }
+        }
+        self->pos++;
+        return tuple;
+    }
+    return NULL;
+}
+
+// static PyObject *
+// ATT_reversed(ATTObject *self) {
+//     return ATT_new(self->bi, !self->reversed);
+// }
+
+static inline PyObject *
+ATT_length_hint(ATTObject *self) {
+    Py_ssize_t len = Py_MAX(0, self->num_rows - self->pos);
+    return PyLong_FromSsize_t(len);
+}
+
+static PyMethodDef ATT_methods[] = {
+    {"__length_hint__", (PyCFunction)ATT_length_hint, METH_NOARGS, NULL},
+    // {"__reversed__", (PyCFunction)ATT_reversed, METH_NOARGS, NULL},
+    {NULL},
+};
+
+static PyTypeObject ATTType = {
+    PyVarObject_HEAD_INIT(NULL, 0)
+    .tp_basicsize = sizeof(ATTObject),
+    .tp_dealloc = (destructor) ATT_dealloc,
+    .tp_iter = (getiterfunc) ATT_iter,
+    .tp_iternext = (iternextfunc) ATT_iternext,
+    .tp_methods = ATT_methods,
+    .tp_name = "arraykit.ATTIterator",
+};
+
+// Given a 2D array, return an iterator of row tuples.
+PyObject *
+array_to_tuple_iter(PyObject *Py_UNUSED(m), PyObject *a)
+{
+    AK_CHECK_NUMPY_ARRAY(a);
+    PyArrayObject *array = (PyArrayObject *)a;
+    int ndim = PyArray_NDIM(array);
+    if (ndim != 1 && ndim != 2) {
+        return PyErr_Format(PyExc_NotImplementedError,
+                "Expected 1D or 2D array, not %i.",
+                ndim);
+    }
+    npy_intp num_rows = PyArray_DIM(array, 0);
+    npy_intp num_cols = -1; // indicate 1d
+    if (ndim == 2) {
+        num_cols = PyArray_DIM(array, 1);
+    }
+    return ATT_new(array, num_rows, num_cols);
+}

src/array_to_tuple.h

@@ -0,0 +1,14 @@
+# ifndef ARRAYKIT_SRC_ARRAY_TO_TUPLE_H_
+# define ARRAYKIT_SRC_ARRAY_TO_TUPLE_H_
+
+# include "Python.h"
+
+// Given a 1D or 2D array, return a 1D object array of tuples.
+PyObject *
+array_to_tuple_array(PyObject *Py_UNUSED(m), PyObject *a);
+
+// Given a 2D array, return an iterator of row tuples.
+PyObject *
+array_to_tuple_iter(PyObject *Py_UNUSED(m), PyObject *a);
+
+# endif // ARRAYKIT_SRC_ARRAY_TO_TUPLE_H_

src/utilities.h

@@ -34,6 +34,17 @@
         }                                                 \
     } while (0)
 
+// Given a PyObject, raise if not an array or is not two dimensional.
+# define AK_CHECK_NUMPY_ARRAY_2D(O)                       \
+    do {                                                  \
+        AK_CHECK_NUMPY_ARRAY(O)                           \
+        int ndim = PyArray_NDIM((PyArrayObject *)O);      \
+        if (ndim != 2) {                                  \
+            return PyErr_Format(PyExc_NotImplementedError,\
+                    "Expected a 2D array, not %i.",       \
+                    ndim);                                \
+        }                                                 \
+    } while (0)
 
 # if defined __GNUC__ || defined __clang__
 # define AK_LIKELY(X) __builtin_expect(!!(X), 1)