scExtensions – Usage¶

Math.calculateAverage¶

Calculates the average of an array of numbers.

Parameters

Parameter	Type	Description
`ary`	`Array<Number>`	Array of numbers to calculate the average for

Return value: Number – the average, or 0 if the array is empty.

var values = [10, 20, 30];
var avg = Math.calculateAverage(values); // Returns 20

Math.isOdd¶

Checks whether a number is odd.

Parameters

Parameter	Type	Description
`value`	`Number`	The number to check

Return value: Boolean – true if the value is odd, otherwise false.

Math.isOdd(3); // true
Math.isOdd(4); // false

Math.isEven¶

Checks whether a number is even.

Parameters

Parameter	Type	Description
`value`	`Number`	The number to check

Return value: Boolean – true if the value is even, otherwise false.

Math.isEven(4); // true
Math.isEven(3); // false

String.prototype.split¶

Splits a string at a specified delimiter and returns an array of the parts.

Parameters

Parameter	Type	Description
`delimiter`	`String`	The delimiter to split the string at

Return value: Array<String> – an array containing the parts of the string.

var parts = "kamera1,kamera2,kamera3".split(",");
// Returns ["kamera1", "kamera2", "kamera3"]

FindAllAlarms¶

Recursively searches through an object (typically DataStore) and collects all alarms.

Parameters

Parameter	Type	Description
`alarms`	`Array`	Empty array that will be populated with the alarms found
`parent`	`String`	Starting string for the path – specify `""`
`obj`	`Object`	The object to search through, typically `DataStore`
`severity`	`Number` (optional)	Filter by a specific severity level. Omit to retrieve all alarms.

var alarms = new Array();

// Get all alarms
scExtensions.FindAllAlarms(alarms, "", DataStore);

// Get only alarms with severity level 10
scExtensions.FindAllAlarms(alarms, "", DataStore, 10);

Each element in the alarms array has the following structure:

Property	Type	Description
`Alarm`	`Object`	Reference to the alarm object
`Name`	`String`	The path to the alarm in `DataStore`
`Active`	`Boolean`	Last known active status

msLeftUntilMidnight¶

Returns the number of milliseconds until midnight, based on the system clock.

Return value: Number – milliseconds remaining until midnight.

var ms = scExtensions.msLeftUntilMidnight();
// Start a timer that expires at midnight
myTimer.start(ms);

bytesToSize¶

Converts a byte value into a human-readable string with an automatically selected unit.

Parameters

Parameter	Type	Description
`bytes`	`Number`	The number of bytes to convert

Return value: String – the formatted value with a unit, e.g. "5.00 MiB".

scExtensions.bytesToSize(5242880);    // "5.00 MiB"
scExtensions.bytesToSize(1073741824); // "1.00 GiB"
scExtensions.bytesToSize(0);          // "0 B"

The script¶

Download scExtensions.js

    //***********************************************//
    // The purpose of this script library
    // is to provide extensions to the script
    // engine.
    // Version 1.0 (2022-06-13)
    // Copyright © 2022 Kentima AB. No rights reserved.
    //***********************************************//

try
{    
    //Calculate average for Array of Numbers
    Math.calculateAverage = function (ary)
    {
        if(ary.length === 0)
            return 0;

        var totalSum = 0;
        for(var i in ary) //Iterate Array object
        {
            if(isNaN(ary[i]))
                throw new Error("Value: '" + ary[i] + "' is not a Number.");
            else
                totalSum += ary[i];
        }
        var average = totalSum / ary.length; //Calculate average

        return average;
    };

    //Check if 'value' is odd
    Math.isOdd = function(value)
    {
        if(isNaN(value))
            throw new Error("Math.isOdd(): value: '" + value + "' is not a Number"); //Throw error if value is not a number

        return (value % 2 == 1); //return if value is odd or not(true/false)
    };

    //Check if 'value' is even
    Math.isEven = function(value)
    {
        if(isNaN(value))
            throw new Error("Math.isEven(): value: '" + value + "' is not a Number");

        return (value % 2 == 0); //return if value is even or not(true/false)
    };

    //Extend String object with split function
    String.prototype.split = function (delimiter)
    {
        if (arguments.length < 1)
        {
            return [this];
        }
        var result = []; //Create Array object
        var buffer = this.slice();
        var dlen   = Math.max(1, delimiter.length);
        while (true) //Do work until nothing left to split
        {
            var ind = buffer.indexOf(delimiter);
            if (ind != -1 && buffer != "")
            {
                result.push(buffer.slice(0, ind));
                buffer = buffer.slice(ind + dlen);
            }
            else
            {
                result.push(buffer);
                return result; //Return Array object
            }
        }
    };

    //Locate all possible alarms in the system
    this.FindAllAlarms = function(alarms, parent, obj, severity)
    {
        for(prop in obj) //Iterate the object you want to find all alarms in, most likely 'DataStore'
        {
            if (obj[prop] instanceof Object)
            {
                this.FindAllAlarms(alarms, parent + prop + ".", obj[prop], severity);
            }
            else
            {
                if(obj.hasOwnProperty("Severity"))
                {
                    //Only add Alarm objects
                    //we can detect them as they have a property named 'Acknowledged'
                    if(((severity == undefined) ? true : (obj.Severity == severity)) && (prop == "Acknowledged"))
                    {
                        alarms[alarms.length] = { "Alarm" : obj, "Name" : parent.substring(0, parent.length-1), "Active" : false };
                    }
                }
            }
        }
    };

    //Get number of milliseconds left until midnight
    this.msLeftUntilMidnight = function()
    {
        var milliseconds = ((23 - System.Clock.Hour) * 3600000) + ((60 - System.Clock.Minute) * 60000) + ((60 - System.Clock.Second) * 1000); //Figure out how many milliseconds there are left until midnight.
        //Debug.Print("msl: " + milliseconds); //For debugging
        return milliseconds;
    };

    //Format bytes
    this.bytesToSize = function(bytes)
    {
        var sizes = ['B', 'KiB', 'MiB', 'GiB', 'TiB' , 'PiB', 'EiB', 'ZiB', 'YiB'];
        if  (bytes == 0) return '0 B';
        if  (isNaN(bytes)) throw new Error ("Value: '" + bytes + "' is not a number");
        var i = Math.floor(Math.log(bytes) / Math.log(1024));
        return (bytes / Math.pow(1024, i)).toFixed(2) + ' ' + sizes[i];
    };
}
catch(e)
{
    Debug.Print("scExtensions: " + e);
}