Determines all local minima of a given function in a given interval.


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Inputs/Outputs

  • cdbl.png accuracy —

    accuracy controls the accuracy of the minimum. The method stops if two consecutive approximations differ no more than the value of accuracy. The default is 1.00E-8.

  • cu16.png step type —

    step type controls the spacing used for the function values. A step type value of 0, fixed function, represents uniformly spaced function values. A value of 1, modified function, represents the optimal step size. In general, modified function leads to more accurate Minima. The default is 0.

  • cu16.png algorithm —

    algorithm specifies the method used by the VI. The default is 0.

    0Golden Section Search (default)
    1Brent with Derivatives
  • cdbl.png start —

    start is the start point of the interval. The default is 0.0.

  • cdbl.png end —

    end is the end point of the interval. The default is 1.0.

  • cstr.png formula —

    formula is a string representing the function under investigation. The formula can contain any number of valid variables.

  • i1ddbl.png Minima —

    Minima is an array of all found minima of formula in the interval (start, end).

  • i1ddbl.png f(Minima) —

    f(Minima) is the function values at the points Minima.

  • iu32.png ticks —

    ticks is the time in milliseconds for the whole calculation.

  • ii32.png error —

    error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.

    • Note If you want to find out the maxima of a function, you must take –function as the inputs. The –f(Minima) are the correct maximal function values.

    The Find All Minima 1D VI finds all minima in the given interval (start, end). To find all minima 1D of f(x) = cos(x²), enter the following values on the front panel:

    • start: -1.0
    • end: 6.0
    • formula: cos(x^2)

    The following illustration shows the plot of f(x). The boxes on the plot are the locations of the minima.

    Note If the start or end values are close to the minimum value, use the modified function step type.

    Examples

    Refer to the following example files included with LabVIEW.

    • labview\examples\Mathematics\Optimization\1D Explorer.vi