Implement vector_lincomb wrapper

min-bindings/C#/ckzg.c

@@ -15,8 +15,30 @@ BLSFieldElement* compute_powers_wrap(const BLSFieldElement *r, uint64_t n) {
   return out;
 }
 
-PolynomialEvalForm* vector_lincomb_wrap(const uint8_t vectors[], const BLSFieldElement scalars[], uint64_t num_vectors, uint64_t vector_len) {
+PolynomialEvalForm* vector_lincomb_wrap(const uint8_t bytes[], const BLSFieldElement scalars[], uint64_t num_vectors, uint64_t vector_len) {
-  return NULL; // TODO
+  PolynomialEvalForm *p = (PolynomialEvalForm*)malloc(sizeof(PolynomialEvalForm));
+  if (p == NULL) return NULL;
+
+  if (alloc_polynomial(p, vector_len) != C_KZG_OK) {
+    free(p);
+    return NULL;
+  }
+
+  BLSFieldElement *vectors = (BLSFieldElement*)calloc(num_vectors * vector_len, sizeof(BLSFieldElement));
+  if (vectors == NULL) {
+    free_polynomial(p);
+    free(p);
+    return NULL;
+  }
+
+  for (uint64_t i = 0; i < num_vectors; i++)
+    for (uint64_t j = 0; j < vector_len; j++)
+      bytes_to_bls_field(&vectors[i * vector_len + j], &bytes[(i * vector_len + j) * 32]);
+
+  vector_lincomb(p->values, vectors, scalars, num_vectors, vector_len);
+
+  free(vectors);
+  return p;
 }
 
 KZGCommitment* g1_lincomb_wrap(const uint8_t bytes[], const BLSFieldElement scalars[], uint64_t num_points) {

min-bindings/python/ckzg.c

@@ -283,7 +283,7 @@ static PyObject* vector_lincomb_wrap(PyObject *self, PyObject *args) {
     return PyErr_NoMemory();
   }
 
-  vector_lincomb(r, vectors, scalars, n, m);
+  vector_lincomb_indirect(r, vectors, scalars, n, m);
 
   free(scalars);
   free(vectors);

min-src/c_kzg_4844.c

@@ -838,7 +838,7 @@ void bytes_to_bls_field(BLSFieldElement *out, const uint8_t bytes[32]) {
 /**
  * Compute linear combinations of a sequence of vectors with some scalars
  */
-void vector_lincomb(fr_t out[], const fr_t* vectors[], const fr_t* scalars[], uint64_t n, uint64_t m) {
+void vector_lincomb_indirect(fr_t out[], const fr_t* vectors[], const fr_t* scalars[], uint64_t n, uint64_t m) {
   fr_t tmp;
   uint64_t i, j;
   for (j = 0; j < m; j++)
@@ -851,6 +851,22 @@ void vector_lincomb(fr_t out[], const fr_t* vectors[], const fr_t* scalars[], ui
   }
 }
 
+/**
+ * Compute linear combinations of a sequence of vectors with some scalars
+ */
+void vector_lincomb(fr_t out[], const fr_t vectors[], const fr_t scalars[], uint64_t n, uint64_t m) {
+  fr_t tmp;
+  uint64_t i, j;
+  for (j = 0; j < m; j++)
+    out[j] = fr_zero;
+  for (i = 0; i < n; i++) {
+    for (j = 0; j < m; j++) {
+      fr_mul(&tmp, &scalars[i], &vectors[i * m + j]);
+      fr_add(&out[j], &out[j], &tmp);
+    }
+  }
+}
+
 /**
  * Calculate a linear combination of G1 group elements.
  *

min-src/c_kzg_4844.h

@@ -109,7 +109,10 @@ void free_trusted_setup(KZGSettings *s);
 
 void bytes_to_bls_field(BLSFieldElement *out, const uint8_t bytes[32]);
 
-void vector_lincomb(BLSFieldElement out[], const BLSFieldElement* vectors[], const BLSFieldElement* scalars[], uint64_t num_vectors, uint64_t vector_len);
+// TODO: probably remove this version
+void vector_lincomb_indirect(BLSFieldElement out[], const BLSFieldElement* vectors[], const BLSFieldElement* scalars[], uint64_t num_vectors, uint64_t vector_len);
+
+void vector_lincomb(BLSFieldElement out[], const BLSFieldElement vectors[], const BLSFieldElement scalars[], uint64_t num_vectors, uint64_t vector_len);
 
 void g1_lincomb(KZGCommitment *out, const KZGCommitment points[], const BLSFieldElement scalars[], uint64_t num_points);