DOUBLE Convert to 64-bit Floating Point

Section: Type Conversion Functions

Usage

Converts the argument to a 64-bit floating point number. The syntax for its use is 
   y = double(x)

where x is an n-dimensional numerical array. Conversion follows the general C rules. Note that both NaN and Inf are both preserved under type conversion.

Example

The following piece of code demonstrates several uses of double. First, we convert from an integer (the argument is an integer because no decimal is present): 
--> double(200)

ans = 

 200 

--> 
quit

In the next example, a single precision argument is passed in (the presence of the f suffix implies single precision). 

--> double(400.0f)

ans = 

 400 

--> 
quit

In the next example, a dcomplex argument is passed in. The result is the real part of the argument, and in this context, double is equivalent to the function real. 

--> double(3.0+4.0*i)

ans = 

 3 

--> 
quit

In the next example, a string argument is passed in. The string argument is converted into an integer array corresponding to the ASCII values of each character. 

--> double('helo')

ans = 

 104 101 108 111 

--> 
quit

In the last example, a cell-array is passed in. For cell-arrays and structure arrays, the result is an error. 

--> double({4})
Error: Cannot convert cell-arrays to any other type.
--> 
quit