static int luaC_lunum_slice(lua_State *L)
{
// The first part of this function extracts a slice of the array 'A' according
// to the convention start:stop:skip. The result is a contiguous array 'B'
// having the same number of dimensions as 'A'.
// ---------------------------------------------------------------------------
size_t Nd0_t, Nd1_t, Nd2_t, Nd3_t;
const Array *A = lunum_checkarray1(L, 1); // the array to resize
size_t *start = (size_t*) lunum_checkarray2(L, 2, ARRAY_TYPE_SIZE_T, &Nd0_t);
size_t *stop = (size_t*) lunum_checkarray2(L, 3, ARRAY_TYPE_SIZE_T, &Nd1_t);
size_t *skip = (size_t*) lunum_checkarray2(L, 4, ARRAY_TYPE_SIZE_T, &Nd2_t);
size_t *squeeze = (size_t*) lunum_checkarray2(L, 5, ARRAY_TYPE_SIZE_T, &Nd3_t);
int Nd0 = (int)Nd0_t, Nd1 = (int)Nd1_t, Nd2 = (int)Nd2_t, Nd3 = (int)Nd3_t;
if (Nd0 != A->ndims || Nd1 != A->ndims || Nd2 != A->ndims || Nd3 != A->ndims) {
return luaL_error(L, "slice has wrong number of dimensions for array");
}
for (int d=0; d<A->ndims; ++d) {
if (start[d] < 0 || stop[d] > A->shape[d]) {
return luaL_error(L, "slice not within array extent");
}
}
Array B = array_new_from_slice(A, start, stop, skip, Nd0);
// The rest of this function deals with squeezing out the size-1 dimensions of
// 'B' which are marked by the 'squeeze' array.
// ---------------------------------------------------------------------------
size_t Nd_new = 0;
for (int d=0; d<Nd0; ++d) Nd_new += !squeeze[d];
// In case we're left with a 0-dimensional (scalar) slice
if (Nd_new == 0) {
_push_value(L, B.dtype, B.data);
return 1;
}
// In case there are any dims to squeeze out
else if (Nd_new != Nd0) {
size_t *shape_new = (size_t*) malloc(Nd_new * sizeof(size_t));
for (int d=0,e=0; d<Nd0; ++d) {
if (B.shape[d] > 1 || !squeeze[d]) {
shape_new[e] = B.shape[d];
++e;
}
}
array_resize_t(&B, shape_new, Nd_new);
free(shape_new);
}
lunum_pusharray1(L, &B);
return 1;
}
static int luaC_lunum_zeros(lua_State *L)
{
if (lua_isnumber(L, 1)) {
const lua_Integer N = luaL_checkinteger(L, 1);
if (N <= 0) { return luaL_error(L, "Invalid size %d", N); }
const ArrayType T = (ArrayType) luaL_optinteger(L, 2, ARRAY_TYPE_DOUBLE);
Array A = array_new_zeros(N, T);
lunum_pusharray1(L, &A);
return 1;
}
else if (lua_istable(L, 1) || lunum_hasmetatable(L, 1, "array")) {
size_t Nd_t;
size_t *N = (size_t*) lunum_checkarray2(L, 1, ARRAY_TYPE_SIZE_T, &Nd_t);
int Nd = (int)Nd_t;
const ArrayType T = (ArrayType) luaL_optinteger(L, 2, ARRAY_TYPE_DOUBLE);
size_t ntot = 1;
for (int d=0; d<Nd; ++d) ntot *= N[d];
Array A = array_new_zeros(ntot, T);
array_resize_t(&A, N, Nd);
lunum_pusharray1(L, &A);
return 1;
}
else {
return luaL_error(L, "argument must be either number, table, or array");
}
}
int luaC_lunum_zeros(lua_State *L)
{
if (lua_isnumber(L, 1)) {
const int N = luaL_checkinteger(L, 1);
const enum ArrayType T = (enum ArrayType) luaL_optinteger(L, 2, ARRAY_TYPE_DOUBLE);
struct Array A = array_new_zeros(N, T);
lunum_pusharray1(L, &A);
return 1;
}
else if (lua_istable(L, 1) || lunum_hasmetatable(L, 1, "array")) {
int Nd;
int *N = (int*) lunum_checkarray2(L, 1, ARRAY_TYPE_INT, &Nd);
const enum ArrayType T = (enum ArrayType) luaL_optinteger(L, 2, ARRAY_TYPE_DOUBLE);
int ntot = 1;
for (int d=0; d<Nd; ++d) ntot *= N[d];
struct Array A = array_new_zeros(ntot, T);
array_resize(&A, N, Nd);
lunum_pusharray1(L, &A);
return 1;
}
else {
luaL_error(L, "argument must be either number, table, or array");
return 0;
}
}
int test_checkarray(lua_State *L)
{
int narg = lua_gettop(L);
for (int i=1; i<=narg; ++i) {
size_t N;
lunum_checkarray2(L, i, ARRAY_TYPE_DOUBLE, &N);
printf("argument %d had length %lu\n", i, N);
}
return 0;
}
static int luaC_lunum_resize(lua_State *L)
{
size_t Nd_t;
Array *A = lunum_checkarray1(L, 1); // the array to resize
size_t *N = (size_t*) lunum_checkarray2(L, 2, ARRAY_TYPE_SIZE_T, &Nd_t);
int Nd = (int)Nd_t;
size_t ntot = 1;
for (int d=0; d<Nd; ++d) ntot *= N[d];
if (A->size != ntot) {
return luaL_error(L, "new and old total sizes do not agree");
}
array_resize_t(A, N, Nd);
return 0;
}
int luaC_lunum_resize(lua_State *L)
{
int Nd;
struct Array *A = lunum_checkarray1(L, 1); // the array to resize
int *N = (int*) lunum_checkarray2(L, 2, ARRAY_TYPE_INT, &Nd);
int ntot = 1;
for (int d=0; d<Nd; ++d) ntot *= N[d];
if (A->size != ntot) {
luaL_error(L, "new and old total sizes do not agree");
return 0;
}
array_resize(A, N, Nd);
return 0;
}