// SPDX-License-Identifier: Apache-2.0
//
// Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au)
// Copyright 2008-2016 National ICT Australia (NICTA)
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ------------------------------------------------------------------------

//! \addtogroup fn_sprandn
//! @{

//! Generate a sparse matrix with a randomly selected subset of the elements
//! set to random values from a Gaussian distribution with zero mean and unit variance
template <typename obj_type>
arma_warn_unused inline obj_type sprandn(
    const uword n_rows, const uword n_cols, const double density,
    const typename arma_SpMat_SpCol_SpRow_only<obj_type>::result* junk = nullptr) {
  arma_debug_sigprint();
  arma_ignore(junk);

  if (is_SpCol<obj_type>::value) {
    arma_conform_check((n_cols != 1), "sprandn(): incompatible size");
  } else if (is_SpRow<obj_type>::value) {
    arma_conform_check((n_rows != 1), "sprandn(): incompatible size");
  }

  obj_type out;

  out.sprandn(n_rows, n_cols, density);

  return out;
}

template <typename obj_type>
arma_warn_unused inline obj_type sprandn(
    const SizeMat& s, const double density,
    const typename arma_SpMat_SpCol_SpRow_only<obj_type>::result* junk = nullptr) {
  arma_debug_sigprint();
  arma_ignore(junk);

  return sprandn<obj_type>(s.n_rows, s.n_cols, density);
}

arma_warn_unused inline sp_mat sprandn(const uword n_rows, const uword n_cols,
                                       const double density) {
  arma_debug_sigprint();

  sp_mat out;

  out.sprandn(n_rows, n_cols, density);

  return out;
}

arma_warn_unused inline sp_mat sprandn(const SizeMat& s, const double density) {
  arma_debug_sigprint();

  sp_mat out;

  out.sprandn(s.n_rows, s.n_cols, density);

  return out;
}

//! Generate a sparse matrix with the non-zero values in the same locations as in the
//! given sparse matrix X, with the non-zero values set to random values from a Gaussian
//! distribution with zero mean and unit variance
template <typename T1>
arma_warn_unused inline SpMat<typename T1::elem_type> sprandn(
    const SpBase<typename T1::elem_type, T1>& X) {
  arma_debug_sigprint();

  typedef typename T1::elem_type eT;

  SpMat<eT> out(X.get_ref());

  arma_rng::randn<eT>::fill(access::rwp(out.values), out.n_nonzero);

  return out;
}

//! @}
