integer arrays can be binned

Author: v923z

code/numpy/compare.c

@@ -6,7 +6,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2020-2021 Zoltán Vörös
+ * Copyright (c) 2020-2025 Zoltán Vörös
  *               2020 Jeff Epler for Adafruit Industries
 */
 
@@ -27,14 +27,69 @@
 mp_obj_t compare_bincount(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_, MP_ARG_REQUIRED | MP_ARG_OBJ, { .u_rom_obj = MP_ROM_NONE} } ,
-        { MP_QSTR_weights, MP_ARG_OBJ, { .u_rom_obj = MP_ROM_NONE } },
-        { MP_QSTR_minlength, MP_ARG_OBJ, { .u_rom_obj = MP_ROM_NONE } },
+        { MP_QSTR_weights, MP_ARG_OBJ | MP_ARG_KW_ONLY, { .u_rom_obj = MP_ROM_NONE } },
+        { MP_QSTR_minlength, MP_ARG_OBJ | MP_ARG_KW_ONLY, { .u_rom_obj = MP_ROM_NONE } },
     };
 
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
-    return mp_const_none;
+    if(!mp_obj_is_type(args[0].u_obj, &ulab_ndarray_type)) {
+        mp_raise_TypeError(MP_ERROR_TEXT("input must be an ndarray"));
+    }
+    ndarray_obj_t *input = MP_OBJ_TO_PTR(args[0].u_obj);
+
+    #if ULAB_MAX_DIMS > 1
+    // no need to check anything, if the maximum number of dimensions is 1
+    if(input->ndim != 1) {
+        mp_raise_ValueError(MP_ERROR_TEXT("object too deep for desired arrayy"));
+    }
+    #endif
+    if((input->dtype != NDARRAY_UINT8) && (input->dtype != NDARRAY_UINT16)) {
+        mp_raise_TypeError(MP_ERROR_TEXT("cannot cast array data from dtype"));
+    }
+
+    // first find the maximum of the array, and figure out how long the result should be
+    uint16_t max = 0;
+    int32_t stride = input->strides[ULAB_MAX_DIMS - 1];
+    if(input->dtype == NDARRAY_UINT8) {
+        uint8_t *iarray = (uint8_t *)input->array;
+        for(size_t i = 0; i < input->len; i++) {
+            if(*iarray > max) {
+                max = *iarray;
+            }
+            iarray += stride;
+        }
+    } else if(input->dtype == NDARRAY_UINT16) {
+        stride /= 2;
+        uint16_t *iarray = (uint16_t *)input->array;
+        for(size_t i = 0; i < input->len; i++) {
+            if(*iarray > max) {
+                max = *iarray;
+            }
+            iarray += stride;
+        }
+    }
+    ndarray_obj_t *result = ndarray_new_linear_array(max + 1, NDARRAY_UINT16);
+
+    // now we can do the binning
+    uint16_t *rarray = (uint16_t *)result->array;
+
+    if(input->dtype == NDARRAY_UINT8) {
+        uint8_t *iarray = (uint8_t *)input->array;
+        for(size_t i = 0; i < input->len; i++) {
+            rarray[*iarray] += 1; 
+            iarray += stride;
+        }
+    } else if(input->dtype == NDARRAY_UINT16) {
+        uint16_t *iarray = (uint16_t *)input->array;
+        for(size_t i = 0; i < input->len; i++) {
+            rarray[*iarray] += 1; 
+            iarray += stride;
+        }
+    }
+
+    return MP_OBJ_FROM_PTR(result);
 }
 
 MP_DEFINE_CONST_FUN_OBJ_KW(compare_bincount_obj, 1, compare_bincount);

code/numpy/compare.h

@@ -6,7 +6,7 @@
  *
  * The MIT License (MIT)
  *
- * Copyright (c) 2020-2021 Zoltán Vörös
+ * Copyright (c) 2020-2025 Zoltán Vörös
 */
 
 #ifndef _COMPARE_