C++ convert a float array to float* (pointer)

Question

I wonder how to convert a float array to a float* I have this situation :

float* floatTab = {12f, 0.5f, 3f};

It gives me an error here. but if I write it like this float floatTab[3] = {12f, 0.5f, 3f};it compiles alright.

This sounds like an XY problem. What are you trying to solve? — juanchopanza
– juanchopanza, Commented Nov 17, 2014 at 11:07
I have a framework that uses a float* i can't pass a float[] so i can't use the code that compiles — Driss Bounouar
– Driss Bounouar, Commented Nov 17, 2014 at 11:08
floatTab will decay to a float* if used as a function parameter, but use the code that "complile [sic] alright" to create the array. — Bathsheba
– Bathsheba, Commented Nov 17, 2014 at 11:09
@DrissBounouar A pointer is not an array. That is the simple explanation for the error. That initialization is for arrays, not a pointer. A pointer is a single, integral value, not a set of values. — PaulMcKenzie
– PaulMcKenzie, Commented Nov 17, 2014 at 11:45

FunkyCat · Accepted Answer · 2014-11-17 11:09:36Z

6

This works OK:

float floatTab[3] = {12f, 0.5f, 3f}; float* ptr = floatTab;

answered Nov 17, 2014 at 11:09

FunkyCat

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1 Comment

Thanks. I was doing some extra changes to the same above code trying to give a reference instead of doing as simple as this.

vincentp · Accepted Answer · 2014-11-17 11:40:10Z

1

Prefer STL containers instead of C arrays (or others RAII-conform classes):

const std::array<float, 3> array = { 1.f, 2.f, 3.f };
float *ptr = &array[0];

Don't forget to include <array> and <initializer_list> to compile this code.

answered Nov 17, 2014 at 11:19

vincentp

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