chenlin/Mujoco_WASM
1
0
Fork 0
Code Issues Pull Requests Actions 2 Packages Projects Releases Wiki Activity

Add utility functions for banded-then-dense symmetric matrices.

Browse Source 
PiperOrigin-RevId: 528757637
Change-Id: I916d843140322c28e857100a6b305a041f704d53
This commit is contained in:
Yuval Tassa
2023-05-02 05:57:22 -07:00
committed by Copybara-Service
parent 2ad82d5998
commit b0bc330b54
13 changed files with 1147 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/engine/engine_util_solve.h
+28 -2
View File
@@ -34,8 +34,7 @@ MJAPI int mju_cholUpdate(mjtNum* mat, mjtNum* x, int n, int flg_plus);
// sparse reverse-order Cholesky decomposition: mat = L'*L; return 'rank'
// mat must have uncompressed layout; rownnz is modified to end at diagonal
int mju_cholFactorSparse(mjtNum* mat, int n, mjtNum mindiag,
int* rownnz, int* rowadr, int* colind,
int mju_cholFactorSparse(mjtNum* mat, int n, mjtNum mindiag, int* rownnz, int* rowadr, int* colind,
mjData* d);
// sparse reverse-order Cholesky solve
@@ -48,6 +47,33 @@ int mju_cholUpdateSparse(mjtNum* mat, mjtNum* x, int n, int flg_plus,
int* rownnz, int* rowadr, int* colind, int x_nnz, int* x_ind,
mjData* d);
// band-dense Cholesky decomposition
// returns minimum value in the factorized diagonal, or 0 if rank-deficient
// mat has (ntotal-ndense) x nband + ndense x ntotal elements
// the first (ntotal-ndense) x nband store the band part, left of diagonal, inclusive
// the second ndense x ntotal store the band part as entire dense rows
// add diagadd+diagmul*mat_ii to diagonal before factorization
MJAPI mjtNum mju_cholFactorBand(mjtNum* mat, int ntotal, int nband, int ndense,
mjtNum diagadd, mjtNum diagmul);
// solve (mat*mat')*res = vec with band-Cholesky decomposition
MJAPI void mju_cholSolveBand(mjtNum* res, const mjtNum* mat, const mjtNum* vec,
int ntotal, int nband, int ndense);
// convert banded matrix to dense matrix, fill upper triangle if flg_sym>0
MJAPI void mju_band2Dense(mjtNum* res, const mjtNum* mat, int ntotal, int nband, int ndense,
mjtByte flg_sym);
// convert dense matrix to banded matrix
MJAPI void mju_dense2Band(mjtNum* res, const mjtNum* mat, int ntotal, int nband, int ndense);
// multiply band-diagonal matrix with vector, include upper triangle if flg_sym>0
MJAPI void mju_bandMulMatVec(mjtNum* res, const mjtNum* mat, const mjtNum* vec,
int ntotal, int nband, int ndense, int nvec, mjtByte flg_sym);
// address of diagonal element i in band-dense matrix representation
MJAPI int mju_bandDiag(int i, int ntotal, int nband, int ndense);
// sparse reverse-order LU factorization, no fill-in (assuming tree topology)
// LU = L + U; original = (U+I) * L; scratch is size n
void mju_factorLUSparse(mjtNum *LU, int n, int* scratch,