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This version covers gsl-2.7, which was recently released.

There are only small changes from version 2.6.5, to cover a small amount 
of extra functionality in gsl-2.7.

John D Lamb

This version fixes a bug that could cause small memory leaks (typically 
four bytes).

-- 
John D Lamb

This version of ccgsl covers just about everything in GSL 2.6. It omits 
a few features, like sorting, that are natively handled in C++.

All the function structs in GSL can now be constructed from function 
objects. Nothing in ccgsl needs to be allocated using malloc() or free() 
functions and where a GSL function takes an array as an argument (eg 
double[]) you can pass a std::vector, std::array or gsl::vector instead.

-- 
John D Lamb

I’ve just released a new version of CCGSL covering version 2.6 of the 
Gnu Scientific Library.

There is quite a bit of new code here. As usual, it wraps GSL functions 
using only C++ header files. There is no library and code built with 
CCGSL should compile except with much older C++ compilers.

The code can still be improved quite a bit. Here are some of the things 
that have been done.

1. The code allows you to create anything that requires a GSL alloc() 
function to be created as a reference class (a bit like a 
std::shared_ptr) so we don’t ever have to remember to free and object: 
free() is called when there are no more references to an object.

2. Most functions are embedded in namespaces, allowing you to use 
shorter names. The naming convention is consistent with GSL except in a 
few cases where that would create a conflict.

3. Most functions have at least minimal documentation, though a few are 
not even documented in the current GSL manual.

4. Where a GSL function expects a pointer to a GSL struct, you can 
nearly always pass an object constructed as in 1 above.

Here are some things that could be done (feel free to volunteer to help).

1. Several GSL functions expect pointers to C functions. But in C++ we 
want to be to pass function objects instead. In only a few cases have I 
managed to implement this.

2. There are some inconsistencies in how CCGSL translates GSL functions 
to either namespace functions, static class functions (for practical 
purposes nearly indistinguishable from namespace functions) and member 
functions. Generally I have tried to use member functions only when they 
are essential or the most obvious place to implement the GSL equivalent. 
Sometimes CCGSL has both a member function and a static class function. 
But improvements and additions would help.

3. There are some inconsistencies in handling of pointers to non-class 
types. Typically CCGSL does this by reference so that the user can see 
the difference between where, for example, a double is wanted rather 
than an array of doubles.

Here are things that CCGSL does not currently plan to do (but feel free 
to say otherwise and help do them if it makes sense).

1. CCGSL avoids operator overloading for adding and multiplying 
matrices, vectors and the like.

2. CCGSL does not include any code that needs to be compiled and 
installed as a library.

-- 
John D Lamb

Dear João;

> I’m new to c++ and I just installed the ccgsl  to substitute my C
> codes with gsl by C++ version. The main reason to want to do this
> change is to avoid the add, div etc functions in big expressions with
> complex numbers.
>
> As far as I could understand ccgsl does´t implement these feature.
> There is any reason to avoid the use of operator overload for the
> arithmetic operators in complex numbers?
>
> Thanks in advance João

There’s no particular reason to avoid this. I’ve tended not to implement 
extensions to what is in GSL. But there’s nothing to stop you doing so.

The following, for example, should work, because namespaces are open.

namespace gsl {
   complex operator+( complex& a, complex& b ){
     return complex::add( a, b );
   }
}

C++14 (and maybe C++11) has a complex template class, which already does 
all of this. So if it’s just complex arithmetic you want, you could 
investigate <complex>. GSL has a few complex functions and some complex 
vectors and matrices. The allocation of vectors and matrices is not as 
efficient as in C++. But there are more standard functions that operate 
on them.

-- 
John D Lamb

Dear ccgsl community,

I’m new to c++ and I just installed the ccgsl  to substitute my C codes with gsl by C++ version.
The main reason to want to do this change is to avoid the add, div etc functions in big expressions with complex numbers.

As far as I could understand ccgsl does´t implement these feature. 
There is any reason to avoid the use of operator overload for the arithmetic operators in complex numbers?

Thanks in advance
João

This version is mainly designed to allow you to drop stride arguments in
functions where an array parameter is required. For example, C++
overloading allows us to create

gsl::mean( double comnst* array, size_t stride, size_t size )

and

gsl::mean( double const* array, size_t size )

functions. Clearly the second is easier to work with, and

gsl::mean( std::vector<double> const& array )

and

gsl::mean( gsl::vector const& array )

are even easier to work with.

In the course of updating these functions, I’ve detected and corrected a
few obscure bugs, mainly in the weirder statistics functions that act on
integer arrays. I’ve also changed the permutation functions to make them
a bit more natural for C++ users and to provide wrappers for
permutations acting on arrays other than gsl::vector objects.

-- 
John D Lamb

This is version 0.99-7 and contains minor additions and bug fixes over
0.99-4 – 0.00-6.

There are three additions:

1. Overloaded functions for const_* functions in the vector classes. For
example, if v is a gsl::vector const object, then v.subvector( i, n )
gives the same result as v.const_subvector( i, n ). This should make it
easier to write code using the same (overloaded) function for const and
non-const objects.

2. real() and imag() vector (view) functions for the vector_complex classes.

3. Bidirectional iterators for the matrix classes. These allow you to
write expressions like the following in C++11:

for( row : matrix ){
  …
}

Inside the for loop row is a vector containing a row of matrix. This is
more expressive but marginally less efficient than using

for( size_t row_index = 0; row_index < matrix.size1(); ++row_index ){
  …
}

together with the matrix.get() and matrix.set() functions.

There is one bug fix, which applies to some of the block, vector and
matrix classes. It prevents the destructor of a default-constructed
object from trying to decrement a null pointer. In practice, the objects
should nearly always be constructed with one or two size parameters,
even if these parameters are zero.

-- 
John D Lamb

I’ve made some minor updates. The main change is the addition of
template versions of functions that take double* or double const*
arguments in GSL. Earlier versions had these for most such functions. I
think the latest releases have them for all such functions.

The effect of these functions is simple: you can pass
std::vector<double>, gsl::vector, or std::array<double> to a function
that in GSL would take a double* or double const* argument. Thus, for
example, instead of

gsl::stats::mean( data, 1, n )

where data is a double* containing n doubles, you can use

gsl::stats::mean( vector ) // default stride of 1 is used

where vector is a gsl::vector or std::vector<double>.

The other changes are mainly to test functions that are not installed.
There are no bug fixes.

-- 
John D Lamb

http://ccgsl.sourceforge.net/index.php

Version 0.99-2 is available. Please feel free to post requests,
suggestions or offers to test or contribute.

-- 
John D Lamb

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