How to initialize float array using vc++?

You cannot do that in a object constructor (if I got you). You have to explicitely initialize it inside the constructor block, for instance:

class MyClass
{
  float fvariable[100];

public:
  MyClass()
  {
    for (int n=0; n < sizeof(fvariable)/sizeof(fvariable[0]); n++)
    {
      fvariable[n] = 0.0;
    }
  }
};

:)

Maybe you just forgot the ;? And don't forget the leading f to tell the compiler you want a float and not a double.
This should work:

//declaration time
float fvariable[100] = { 0.0f };

//you can't do that.
//fvariable[100] = { 0.0f };

//Or you can do as CPallini suggests:
for (int i = 0; i < 100; n++)
    fvariable[i] = 0.0f;

But they are other ways...

Hi,
You should get acquainted with initializer lists[^] as they are generalized in C++0x.

To initialize a C array member in a C++ class constructor, (which is poor design), swap it with a default initialized one, for instance:

#include <algorithm>
class MyClass
{
  float fvariable[100];

public:
  MyClass()
  {
      float temp[100] = {0};
      std::swap(fvariable, temp);
  }
};

If you use a modern C++ compiler (which you should) as VC2010 or gcc 4.5 replace your C array by a C++ std::array, and it will be default initialized:

#include <array>
class MyClass
{
  std::array<float, 100> fvariable; // default initialized to all zeroes

public:
  MyClass()
  {}
};

cheers,
AR