# zeroCrossings(a)

Determines the points at which a function crosses the X axis: the zero crossings.

### Syntax

o_zeroCrossings(a)
  a: array 1D real OR Waveform
  return: array Real - the estimated points where the array or waveform cross the X axis
  waveform input > output is in time units
  mapped array input > output is in mapped units
  unmapped array > output is in index units

### Usage

The real roots of a function lie on the X axis and can be estimated by this function since it locates zero crossings.

### Location

menu: veeos ==> Signal Processing ==> Zero Crossings

library: sigLib

### Example

see veeos example

### Notes

For maximum robustness the underlying algorithm uses a grid search and then linear interpolation to find the zero crossing. Either direction of crossing is found.

### Reference

### Dependencies

### Supported On

VEE 7.0+, all platforms

### See Also

© 2015-2021. All Rights Reserved. Stan Bischof (stan@worldbadminton.com). Last updated 09 August 2021 18:33.