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.
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 = <double> - size: [1 1] 200.000000000000
In the next example, a single precision argument is passed in (the presence of the f suffix implies single precision).
--> double(400.0f) ans = <double> - size: [1 1] 400.000000000000
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 =
<double> - size: [1 1]
3.000000000000000
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 =
<double> - size: [1 4]
Columns 1 to 2
104.000000000000 101.000000000000
Columns 3 to 4
108.000000000000 111.000000000000
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.
at built-in function double