Two real time series chart

General
1

i find this example.
https://flows.nodered.org/flow/36f2de38ed4bb62cf3a5e8fdc76d779e

but can some explain why?
many thanks

2

Explain what about it?
Unless you need to do what that flow does then it is not relevant to your problem.
What exactly are you trying to do?

3

@Colin , hi i want to display both real time series curve in one chart.
that is two real time curve?
i have try

var total = msg.payload.data.count;
for(var i = 0;i<=20 ; i++){
   temp.push({"x":msg.payload.data.datastreams[0].datapoints[i].at, "y":parseInt(msg.payload.data.datastreams[0].datapoints[i].value.substr(-6))/10
});
   wind.push({"x":msg.payload.data.datastreams[0].datapoints[i].at, "y":parseInt(msg.payload.data.datastreams[0].datapoints[i].value.substr(9,11))/100
});
}
msg1.topic = "A"
msg1.payload = [{
"series": ["WindSpeed"],
"data": [ temp],
"labels": [""]
}]

msg2.topic = "B"
msg2.payload = [{
"series": ["Temperature"],
"data": [ wind],
"labels": [""]
}]

return msg1,msg2;

but without success.

and this is my single real time curve with result from API

let data =[];
//for (let prop in msg.payload) {
//    data.push({"x":msg.payload.data.datastreams[1].datapoints[prop].value, "y":msg.payload[prop].at});
//}

for (var i = 0; i<total; i++){
    data.push({"x":msg.payload.data.datastreams[0].datapoints[i].at, "y":parseInt(msg.payload.data.datastreams[0].datapoints[i].value.substr(-6))/10
});
}
//payload.data.datastreams[1].datapoints[0].value


msg.data = data;
return msg;


series = [];
data = [];
data_1 = [];

labels = [];
var msg1 = {};
var msg2 = {};
series.push("Count","test","abc");
labels.push("Labels");
data.push(msg.data);
msg.payload = [{"series":series, "data":data,"labels": labels}];

//series.push("Count","test","abc");
//labels.push("Labels");
//data.push(msg2.data);
//msg2.payload = [{"series":series, "data":data,"labels": labels}];


return msg;
4

Read the node red docs page on Writing Functions to see how to correctly return two messages.

6

i have successful in sending two messgae,
by modifyingreturn [[msg1,msg2]];
however, the chart is now displaying only the chart on ONLY last msg,

but not both
any more hints , thanks

7

You don't need to send two separated messages. You have data for two series.
Do following

msg.payload = [{
"series": ["WindSpeed","Temperature"],
"data": [ wind,temp],
"labels": [""]
}]
8

thanks~
it works well

9

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.