vDSP_svemg
Calculates the sum of magnitudes in a single-precision vector.
Declaration
extern void vDSP_svemg(const float *__A, vDSP_Stride __IA, float *__C, vDSP_Length __N);Parameters
- __A:
Single-precision real input vector.
- __IA:
Stride for
A. - __C:
Single-precision real output scalar.
- __N:
The number of elements to process.
Discussion
This function calculates the sum of magnitudes of the first N elements of A and writes the result to C:
[Image]
The operation is:
C[0] = sum(|A[n]|, 0 <= n < N);The following code shows an example of using vDSP_svemg:
let stride = vDSP_Stride(1)
let a: [Float] = [-1.5, 2.25, 3.6,
0.2, -0.1, -4.3]
let n = vDSP_Length(a.count)
var c: Float = .nan
vDSP_svemg(a,
stride,
&c,
n)
// Prints "sum of magnitudes 11.9500"
print(String(format: "sum of magnitudes %.4f", c))