theta = angle(z) returns
the phase angle in the interval [-π,π] for each
element of a complex array z. The angles in theta are
such that z = abs(z).*exp(i*theta).

Create a signal that consists of two sinusoids of frequencies 15 Hz and 40 Hz. The first sinusoid has a phase of $-\pi /4$, and the second has a phase of $\pi /2$. Sample the signal at 100 Hz for one second.

fs = 100;
t = 0:1/fs:1-1/fs;
x = cos(2*pi*15*t - pi/4) - sin(2*pi*40*t);

Compute the Fourier transform of the signal. Plot the magnitude of the transform as a function of frequency.

y = fft(x);
z = fftshift(y);
ly = length(y);
f = (-ly/2:ly/2-1)/ly*fs;
stem(f,abs(z))
xlabel 'Frequency (Hz)'
ylabel '|y|'
grid

Compute the phase of the transform, removing small-magnitude transform values. Plot the phase as a function of frequency.

Input array, specified as a scalar, vector, matrix, or multidimensional array. When
the elements of z are non-negative real numbers,
angle returns 0. When the elements of z are
negative real numbers, angle returns π.

Data Types: double | single Complex Number Support: Yes

Algorithms

angle takes a complex number z = x +
iy and uses the atan2 function to compute the angle between
the positive x-axis and a ray from the origin to the point
(x,y) in the xy-plane.

Extended Capabilities

Tall Arrays Calculate with arrays that have more rows than fit in memory.

This function fully supports tall arrays. For
more information, see Tall Arrays.

C/C++ Code Generation Generate C and C++ code using MATLAB® Coder™.

GPU Code Generation Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

GPU Arrays Accelerate code by running on a graphics processing unit (GPU) using Parallel Computing Toolbox™.

This function fully supports GPU arrays. For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Distributed Arrays Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

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