diff options
Diffstat (limited to 'builtins/array.c')
| -rw-r--r-- | builtins/array.c | 62 |
1 files changed, 25 insertions, 37 deletions
diff --git a/builtins/array.c b/builtins/array.c index 69d5cff1..1c31be80 100644 --- a/builtins/array.c +++ b/builtins/array.c @@ -261,51 +261,39 @@ public array_t Array$sample(array_t arr, int64_t n, array_t weights, const TypeI return selected; } -public array_t Array$slice(array_t *array, int64_t first, int64_t length, int64_t stride, const TypeInfo *type) +public array_t Array$from(array_t *array, int64_t first, int64_t last) { - if (stride > MAX_STRIDE || stride < MIN_STRIDE) - fail("Stride is too big: %ld", stride); + if (first < 0) + first = array->length + first + 1; - if (stride == 0 || length <= 0) { - // Zero stride + if (last < 0) + last = array->length + last + 1; + + if (first < 1 || first > array->length || last < first) return (array_t){.atomic=array->atomic}; - } else if (stride < 0) { - if (first == INT64_MIN) first = array->length; - if (first > array->length) { - // Range starting after array - int64_t residual = first % -stride; - first = array->length - (array->length % -stride) + residual; - } - if (first > array->length) first += stride; - if (first < 1) { - // Range outside array - return (array_t){.atomic=array->atomic}; - } - } else { - if (first == INT64_MIN) first = 1; - if (first < 1) { - // Range starting before array - first = first % stride; - } - while (first < 1) first += stride; - if (first > array->length) { - // Range outside array - return (array_t){.atomic=array->atomic}; - } - } - if (length > array->length/labs(stride) + 1) length = array->length/labs(stride) + 1; - if (length < 0) length = -length; + if (last > array->length) + last = array->length; + + return (array_t){ + .atomic=array->atomic, + .data=array->data + array->stride*(first-1), + .length=last - first + 1, + .stride=array->stride, + .data_refcount=array->data_refcount, + }; +} - // Saturating add: - array->data_refcount |= (array->data_refcount << 1) | 1; +public array_t Array$by(array_t *array, int64_t stride) +{ + if (stride == 0) + return (array_t){.atomic=array->atomic}; - int64_t item_size = get_item_size(type); return (array_t){ .atomic=array->atomic, - .data=array->data + item_size*(first-1), - .length=length, - .stride=(array->stride * stride), + .data=(stride < 0 ? array->data + (array->stride * (array->length - 1)) : array->data), + .length=(stride < 0 ? array->length / -stride : array->length / stride) + ((array->length % stride) != 0), + .stride=array->stride * stride, .data_refcount=array->data_refcount, }; } |
