# atan2#

## Purpose#

Computes an angle from an x, y coordinate.

## Format#

z = atan2(y, x)#
Parameters:
• y (matrix) – NxK matrix or P-dimensional array where the last two dimensions are NxK, the y coordinate.

• x (matrix) – LxM matrix or P-dimensional array where the last two dimensions are LxM, ExE conformable with y, the x coordinate.

Returns:

z (matrix) – max(N,L) by max(K,M) matrix or P-dimensional array where the last two dimensions are max(N,L) by max(K,M).

## Examples#

// Create the sequence -π, -π/2, 0, π/2, π
x = seqa(-pi, pi/2, 5);
y = 1;

zpol = atan2(y, x);
zdeg = zpol*(180/pi);

print "x = " x;
print "zpol = " zpol;
print "zdeg = " zdeg;


After the code above:

   -3.142         2.833         162.343
-1.571         2.575         147.518
x = 0.000  zpol = 1.571  zdeg =  90.000
1.571         0.567          32.482
3.142         0.308          17.657


## Remarks#

Given a point x, y in a Cartesian coordinate system, atan2() will give the correct angle with respect to the positive x-axis. The answer will be in radians from $$-\pi$$ to $$+\pi$$.

To convert radians to degrees, multiply by $$180/π$$.

atan2() operates only on the real component of x, even if x is complex.