How to setup and event on rate of change?

phildunlap

Data will be coming from it, won't it? :D

A solution some people use for noisy data, to avoid what I was talking about, is to just use averages from time periods to compare instead of raw data, so,

var period = 300000 //5*60*1000 Five minutes
var now = new Date();
var start = now.getTime() - period;
var middle = now.getTime() - period/2;
if( Math.abs( p.getStats(middle, now).average - p.getStats(start, middle).average ) > 5 ) //Threshhold
  return true;
return false;

Depending on your needs or thoughts on your data.

v8dave

Just trying this now and when I input the script and then click save, I get this error at the bottom.

invalid return
at line -1

I've selected a suitable data point and set its name to p for this test.

phildunlap

Are you using the scripts as posted or as they arrived in an email notification?

I am able to run all of these with a numeric point for p. That looks like a syntax error, which I think I would get regardless of the code path.

v8dave

Hi Phil, I am using a numerical data point. Here is the screen capture. I modified the script as I only need to detect a falling trend.!!

0_1469686311138_script.png

phildunlap

it looks like you are using the scripting data source, instead of a meta data source and putting these scripting in a meta data point.

Scripts are intended for a multiple-output control loop. Scripting data source scripts don't contain return statements, they set a point's value with p.set(value, time) or just p.set(value) for the current time.

This kind of thing, where we're producing a single answer from perhaps multiple inputs, should be a meta point.

v8dave

Ah yes, so I was. Just trying it now but there is an error about a null value on line 4 which seems strange because it would not get to this line unless there was data.

var data = bbl1.pointValuesSince(new Date().getTime() - 5*60*1000); //Five minutes in milliseconds
if( data.length <= 1 ) //we have the same edge conditions for our range
   return false;
var firstValue = data[0];
var changeThreshhold = -20; //so, this would mean that if any point in the period it is more than
for( var k = 1; k < data.length; k+=1 ) {
  if( firstValue.value - data[k].value < changeThreshhold)
    return true;
}
return false;

phildunlap

That is odd....
I would put print(data) at line 2 to investigate.

v8dave

I've added that but where do I see the output from this?

phildunlap

It would be below the script window, if it ran, where you saw the error. If it didn't, I wonder if you have a global script declared? The global scripts page is this icon:

v8dave

I don't have that icon. Is this a module I need to install or a setting somewhere?

v8dave

I found the module and installed it and the icon is now present. My scripts still don't seem the be running as there is no output from the print(data) statement.

phildunlap

No, I was curious if that's where the error was occurring, not telling you that you needed to install it.

Do you get the same error from a very simple script, perhaps just...

return false;

Are you sure your point is in the context as bbl1 (b - b - lower case L - numeral 1)?

v8dave

I am assuming that the variable is based on the area I circled?

phildunlap

Yeah, just checking. That script I posted surely runs for me, here's a version of yours with lots of print statements, maybe it will help find the issue?

print("bbl1:");
print(bbl1);
var data = bbl1.pointValuesSince(new Date().getTime() - 5*60*1000); //Five minutes in milliseconds
print("data:");
print(data);
if( data.length <= 1 ) //we have the same edge conditions for our range
   return false;
print("Passed the length condition...");
var firstValue = data[0];
var changeThreshhold = -20; //so, this would mean that if any point in the period it is more than
for( var k = 1; k < data.length; k+=1 ) {
  if( firstValue.value - data[k].value < changeThreshhold)
    return true;
}
return false;

If you see no output, I encourage you to 1) check for updates, 2) clear your browsers cache, 3) delete Mango/work/jsp and then try again.

v8dave

Hi Phil, it doesn't seem to run. Nothing appears from the debug. I also deleted the jsp directory and still the same.

phildunlap

Are you getting errors in the log, or just on the script's page? Is it still reporting null at line 4? Did you try a very simple script, just

return false;

And see if it reports success result=false?

Well, would it be possible for you to email me the JSON for your Mango and I'll try to find the problem locally? I'd like your whole configuration.

v8dave

Looking at the log file, it is still failing at this line.

var firstValue = data[0];

ERROR 2016-07-29 07:39:00,004 (com.serotonin.m2m2.meta.JavaScriptPointLocatorRT.executeImpl:54) - sun.org.mozilla.javascript.EvaluatorException: Java class "java.util.ArrayList" has no public instance field or method named "0". (<Unknown Source>#9) in <Unknown Source> at line number 9 in <Unknown Source> at line number 9

I export and send you the file.

phildunlap

It works fine for me, so, I wonder if it's a Java version issue.

Judging from that error message, I would try using data.get(0) instead of data[0]

Can you run "java -version" on the command line and report the result?

v8dave

It's running on a Centos system and the "java -version" command gives me this error.

Error occurred during initialization of VM
Could not reserve enough space for object heap
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.

I have Mango running as a service on this machine. Java is install and running otherwise Mango won't run.

v8dave

With .get(0) I get this error.

ERROR 2016-07-29 08:13:13,576 (com.serotonin.m2m2.meta.JavaScriptPointLocatorRT.executeImpl:54) - sun.org.mozilla.javascript.EcmaError: TypeError: Cannot find function get in object {minimumValue: 99.05402923333332, minimumTime: 1469804893540, maximumValue: 99.568, maximumTime: 1469805193538, average: 99.15065249671122, sum: 397.38296884523055, count: 4, delta: 0.5139707666666737, integral: 29745.195749013365, firstValue: 99.05402923333332, firstTime: 1469805036550, lastValue: 99.568, lastTime: 1469805193538, periodStartTime: 1469804893540, periodEndTime: 1469805193540}. (<Unknown Source>#9) in <Unknown Source> at line number 9 in <Unknown Source> at line number 9 
javax.script.ScriptException: sun.org.mozilla.javascript.EcmaError: TypeError: Cannot find function get in object {minimumValue: 99.05402923333332, minimumTime: 1469804893540, maximumValue: 99.568, maximumTime: 1469805193538, average: 99.15065249671122, sum: 397.38296884523055, count: 4, delta: 0.5139707666666737, integral: 29745.195749013365, firstValue: 99.05402923333332, firstTime: 1469805036550, lastValue: 99.568, lastTime: 1469805193538, periodStartTime: 1469804893540, periodEndTime: 1469805193540}. (<Unknown Source>#9) in <Unknown Source> at line number 9 in <Unknown Source> at line number 9