Installing and using the Matlab interfaces

To use the Matlab interfaces, the C library and the Mex programs must be built according to the instructions of this page. Both C and Matlab mex compilers are required.

Compiling

Makefiles are provided to build the code. However the locations of SSHT, FFTW and optionally GSL must be defined in Bash/Shell. In FLAG the default Makefile will look at these symbols in Bash/Shell. Alternatively you may declare them explicitely in the first section of the makefile. The compilers and their options may also be changed in the Makefile.

Once you have set the Makefile up for your system, the C library and the Matlab interfaces for FLAG may be compiled by running: 

 >> make matlab

To tidy up all temporary files and objects run: 

 >> make tidy

To remove all compiled files and programs run: 

 >> make clean


Source code documentation

The Matlab documentation is available here. Also, all Matlab routines are self documenting so that documentation can be accessed through the help command in Matlab, as discussed below.


Testing and using the interfaces

Once the Matlab interface is built, you must have both FLAG/src/main/matlab and ssht/src/matlab in your path in order to run the Matlab functions. A number of Matlab functions and demos illustrating their use are provided.

Functions

A list of the high-level Matlab functions, with brief descriptions, is given here: 

  flag_analysis
  Compute the Fourier-Laguerre transform of a 3D signal sampled on the ball.

  flag_synthesis
  Reconstruct a 3D signal on the ball from its Fourier-Laguerre transform.

  flag_sampling
  Compute the exact sampling scheme on the ball.

  flag_plot_sampling
  Plot the exact sampling scheme on the ball.

  flag_sbessel_basis
  Compute the spherical Bessel function at some order ell on a grid of radii.

  slag_analysis
  Compute the spherical Laguerre transform of a signal on the radial line.

  slag_synthesis
  Reconstruct a radial signal from its spherical Laguerre transform.

  slag_sampling
  Compute the exact sampling scheme on the radial half-line.

  slag_basis
  Compute the spherical Laguerre functions up to some order N on a grid of radii.

  slag_gausslaguerre_quadrature
  Compute the nodes of the exact quadrature of the radial half-line.

To access the documentation for each function in Matlab, simply run: 

 >> help <function>

where <function> is the function name.

Demos

A number of demos are provided to illustrate the use of the Matlab interface. 

  flag_fulltest
  Run and test all functionalties of the wavelet transform (MW sampling)

  flag_demo1 
  Plot the radial sampling, the radial basis functions and the  
  3D sampling theorem on the ball.