====ValueSummary====

Captures key values from a table into the frame.

===Parameters===

^Name^Default^Meaning^
|method|avg|**avg**, **max**, **min** or **total**|
|columns||Restrict the summary to only specific columns|
|prefix||Text to add before the name of each value|
|suffix||Text to add after the name of each value|
|named||Override the name for the Captured attribute|
|where||A condition that must be met for the value to be analysed|
|split||Break the summaries up based on a value|

===Special Rate Parameters===

|rate|The value is a //rate//, controlled by a column value|
|timebase|The number of seconds per time unit|

===Description===

This function performs simple analytic functions on some (or all) of the columns in a table and captures them.

This can be used to capture //min//, //max//, //avg// or //total// values across the different columns of your tables.

If you don't specify which columns the analytic should be performed on, it will be applied to **all** columns. 

===Example===

If the frame contains the following table...

^Time^Speed^Temperature^
|10:00|0|100|
|10:10|25|100|
|10:20|50|100|
|10:30|75|100|
|10:40|100|100|

<code javascript>
{
   "type": "valuesummary",
    "method": "avg"
}
</code>

Your frame would then contain...

^Name^Value^
|Average Speed|50|
|Average Temperature|100|

===Working with Rates===

If your values represent a //rate// (such as an amount of **production per minute**), you can use the two special parameters ('rate' and 'timebase') to change how the analytics are performed.

The first is //rate//, which should be the name of the column where the **speed** or **flow rate** of your process can be read. 

The next is //timebase//, which lets specify the number of seconds that each 'rate' measurement represents. For example, this would be '60' if your rate measurement is in units-per-minute, or 3600 if it's in units-per-hour.

So - for example - if you have scale giving you **weight per meter** and a sensor giving you **meters per minute**, you could use the following configuration...

<code javascript>
{
   "type": "valuesummary",
   "columns": ["Scale.Weight"],
   "rate": "Line.Speed",
   "multiplier": 60,
   "mode": "total"
}
</code>

...which would give you a "Total Scale.Weight" figure that contained the total weight of manufactured product.

If you simply want a total of the rate (ie, you wanted a total of the number of meters of production), use the name in both the column **and** the rate properties. For example...

<code javascript>
{
   "type": "valuesummary",
   "columns": ["Line.Speed"],
   "rate": "Line.Speed",
   "multiplier": 60,
   "mode": "total"
}
</code>

===Splitting Results===

In some cases, you might want **several different** summary values.

^Time^Speed^Product^
|10:00|0|Chocolate|
|10:10|25|Strawberry|
|10:20|50|Blueberry|
|10:30|75|Caramel|
|10:40|100|Bananna|

<code javascript>
{
   "type": "valuesummary",
    "method": "avg",
   "split": "Product"
}
</code>

Your frame would then contain...

^Name^Value^
|Average Chocolate Speed|0|
|Average Strawberry Speed|25|
|Average Blueberry Speed|50|
|Average Caramel Speed|75|
|Average Bananna Speed|100|

===Naming===

This layer gives you control of the attributes written to the Capture.

Without a 'named' parameter, your full value name will be...

//<prefix><split><name><suffix>//, where the name is made up of //<function><column-name>//

With the example data below...

^Temperature^Mode^
|10|Stopped|
|20|Running|

...asking for an average temperature and using no other parameters would give you **AvgTemperature** with a value of 15.

Where specifying...

^Attribute^Value^
|prefix|Average |
|splitby|Mode|
|named| Temperature|
|suffix| C|

...would give you both **Average Stopped Temperature C** and **Average Running Temperature C**, with values of 10 and 20 respectively.