SPARSE_GRID_CC_DATASET
Create Clenshaw-Curtis Sparse Grid Dataset

SPARSE_GRID_CC_DATASET is a FORTRAN77 program which creates a Clenshaw-Curtis sparse grid dataset.

Usage:

sparse_grid_cc_dataset dim_num level_max

• dim_num is the spatial dimension, typically between 2 and 10;
• level_max is the sparse grid level, typically between 0 and 6, which controls the number of points in the grid. The 1D rules used will have order 2^(level_max)+1.

Each sparse grid is stored using the "quadrature rule" format, that is, as three files:

• an "R" or "region" file, which lists two points that bound the region;
• a "W" or "weight" file, which lists the weight for each abscissa;
• an "X" or "abscissa" file, which lists the abscissas of the rule.

The abscissas are ordered to respect the natural nesting of the sparse grids by level. That is, the file of level 3 points begins by listing the points in the level 2 grid.

Licensing:

The code described and made available on this web page is distributed under the GNU LGPL license.

Languages:

SPARSE_GRID_CC_DATASET is available in a C version and a C++ version and a FORTRAN77 version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

MONTE_CARLO_RULE, a FORTRAN90 program which generates a dataset of N random M-dimensional points, regards it as a quadrature rule for the unit hypercube, and writes out three files of information.

SGMGA, a FORTRAN90 library which creates sparse grids based on a mixture of 1D quadrature rules, allowing anisotropic weights for each dimension.

SMOLPACK, a C library which implements Novak and Ritter's method for estimating the integral of a function over a multidimensional hypercube using sparse grids.

SPARSE_GRID_CC, a FORTRAN77 library which creates a Clenshaw-Curtis sparse grid.

SPARSE_GRID_CC, a dataset directory which contains examples of Clenshaw-Curtis sparse grids.

SPARSE_GRID_GL_DATASET, a FORTRAN90 program which creates a Gauss-Legendre sparse grid and write the data to three files.

SPARSE_GRID_HW, a FORTRAN77 library which creates sparse grids based on Gauss-Legendre, Gauss-Hermite, Gauss-Patterson, or a nested variation of Gauss-Hermite rules, by Florian Heiss and Viktor Winschel.

SPARSE_GRID_LAGUERRE_DATASET, a FORTRAN90 program which creates a Gauss-Laguerre sparse grid and write the data to three files.

SPARSE_GRID_MIXED_DATASET, a FORTRAN90 program which creates a sparse grid dataset based on a mixture of 1D rules.

SPARSE_GRID_OPEN_DATASET, a FORTRAN90 program which creates a sparse grid dataset based on open rules (Fejer 2, Gauss-Patterson, Newton-Cotes-Open).

TOMS847, a MATLAB program which uses sparse grids to carry out multilinear hierarchical interpolation. It is commonly known as SPINTERP, and is by Andreas Klimke.

Reference:

1. Volker Barthelmann, Erich Novak, Klaus Ritter,
   High Dimensional Polynomial Interpolation on Sparse Grids,
   Advances in Computational Mathematics,
   Volume 12, Number 4, 2000, pages 273-288.
2. Thomas Gerstner, Michael Griebel,
   Numerical Integration Using Sparse Grids,
   Numerical Algorithms,
   Volume 18, Number 3-4, 1998, pages 209-232.
3. Albert Nijenhuis, Herbert Wilf,
   Combinatorial Algorithms for Computers and Calculators,
   Second Edition,
   Academic Press, 1978,
   ISBN: 0-12-519260-6,
   LC: QA164.N54.
4. Fabio Nobile, Raul Tempone, Clayton Webster,
   A Sparse Grid Stochastic Collocation Method for Partial Differential Equations with Random Input Data,
   SIAM Journal on Numerical Analysis,
   Volume 46, Number 5, 2008, pages 2309-2345.
5. Sergey Smolyak,
   Quadrature and Interpolation Formulas for Tensor Products of Certain Classes of Functions,
   Doklady Akademii Nauk SSSR,
   Volume 4, 1963, pages 240-243.
6. Dennis Stanton, Dennis White,
   Constructive Combinatorics,
   Springer, 1986,
   ISBN: 0387963472,
   LC: QA164.S79.

Source Code:

• sparse_grid_cc_dataset.f, the source code.
• sparse_grid_cc_dataset.sh, commands to compile the source code.

Examples and Tests:

Here are the three quadrature files created by the command

sparse_grid_cc_dataset 2 3

• sparse_grid_cc_dataset_output.txt, the output file.
• cc_d2_level3_r.txt, the "R" or "region" file.
• cc_d2_level3_w.txt, the "W" or "weight" file.
• cc_d2_level3_x.txt, the "X" or "abscissa" file.

List of Routines:

• MAIN is the main program for SPARSE_GRID_CC_DATASET.
• MAIN_SUB allocates memory for the main program.
• ABSCISSA_LEVEL_CLOSED_ND: first level at which given abscissa is generated.
• CC_ABSCISSA returns the I-th abscissa for the Clenshaw Curtis rule.
• CC_WEIGHTS computes Clenshaw Curtis weights.
• COMP_NEXT computes the compositions of the integer N into K parts.
• GET_UNIT returns a free FORTRAN unit number.
• I4_CHOOSE computes the binomial coefficient C(N,K).
• I4_MODP returns the nonnegative remainder of integer division.
• I4_MOP returns the I-th power of -1 as an I4 value.
• I4VEC_EQ is true if every pair of entries in two I4VECs is equal.
• I4VEC_PRODUCT returns the product of the entries of an I4VEC.
• INDEX_TO_LEVEL_CLOSED determines the level of a point given its index.
• LEVEL_TO_ORDER_CCS: level to order for CCS rule.
• LEVEL_TO_ORDER_CLOSED converts a level to an order for closed rules.
• LEVELS_CLOSED_INDEX computes closed grids with 0 .le. LEVEL .le. LEVEL_MAX.
• MULTIGRID_INDEX0 returns an indexed multidimensional grid.
• MULTIGRID_SCALE_CLOSED renumbers a grid as a subgrid on a higher level.
• PRODUCT_WEIGHTS_CC: Clenshaw Curtis product rule weights.
• R8_HUGE returns a "huge" R8.
• R8MAT_TRANSPOSE_PRINT_SOME prints some of an R8MAT transposed.
• R8MAT_WRITE writes a R8MAT file.
• R8VEC_DIRECT_PRODUCT2 creates a direct product of R8VEC's.
• R8VEC_DOT_PRODUCT finds the dot product of a pair of R8VEC's.
• R8VEC_PRINT_SOME prints "some" of an R8VEC.
• S_TO_I4 reads an I4 from a string.
• R8VEC_SUM sums the entries of an R8VEC.
• S_BLANK_DELETE removes blanks from a string, left justifying the remainder.
• S_LEN_TRIM returns the length of a string to the last nonblank.
• SPARSE_GRID_CC computes a sparse grid of Clenshaw Curtis points.
• SPARSE_GRID_CC_INDEX indexes the points forming a sparse grid.
• SPARSE_GRID_CC_WEIGHTS gathers the weights.
• SPARSE_GRID_CCS_SIZE sizes a sparse grid using Clenshaw Curtis Slow rules.
• SPARSE_GRID_CC_SIZE sizes a sparse grid using Closed Fully Nested rules.
• TIMESTAMP prints out the current YMDHMS date as a timestamp.
• VEC_COLEX_NEXT2 generates vectors in colex order.

You can go up one level to the FORTRAN77 source codes.