I want to compare a variable from the message two set values in a function but I can't describe it (I'm bad with the syntax) I imagine it like this:
if (msg.payload.current_value >= 5 && msg.payload.current_value =< 10) {
msg.payload = "high;}
else msg.payload = "low";
return msg;
Is this correct?
Hi @devifast
Use the already provided Nodes 
[{"id":"c2c09c2b70fcbd89","type":"inject","z":"2d7bf6e3.84c97a","name":"Hgh","props":[{"p":"payload.current_value","v":"6","vt":"num"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","x":1250,"y":380,"wires":[["156b5bbf15a56727"]]},{"id":"156b5bbf15a56727","type":"switch","z":"2d7bf6e3.84c97a","name":"","property":"payload.current_value","propertyType":"msg","rules":[{"t":"btwn","v":"5","vt":"num","v2":"10","v2t":"num"},{"t":"else"}],"checkall":"true","repair":false,"outputs":2,"x":1410,"y":420,"wires":[["5b09369544891d85"],["5837258fc297d9cb"]]},{"id":"5b09369544891d85","type":"change","z":"2d7bf6e3.84c97a","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"high","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":1600,"y":380,"wires":[["e09cf838760d0c3b"]]},{"id":"5837258fc297d9cb","type":"change","z":"2d7bf6e3.84c97a","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"low","tot":"str"}],"action":"","property":"","from":"","to":"","reg":false,"x":1600,"y":420,"wires":[["e09cf838760d0c3b"]]},{"id":"aafe0b4487fe833a","type":"inject","z":"2d7bf6e3.84c97a","name":"Low","props":[{"p":"payload.current_value","v":"4","vt":"num"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","x":1250,"y":440,"wires":[["156b5bbf15a56727"]]},{"id":"e09cf838760d0c3b","type":"debug","z":"2d7bf6e3.84c97a","name":"debug 384","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":1770,"y":400,"wires":[]}]
For comparisons and setting values, the switch and change nodes are all you need.
Awesome! But how to describe it in a function. I know your solution works, but I'm trying to do things in a function. it's neat and I want to learn.
if(msg.payload.current_value >= 5 && msg.payload.current_value <= 10){
return {payload:'high'}
} else {
return {payload:'low'}
}
OR
if(msg.payload.current_value >= 5 && msg.payload.current_value <= 10){
msg.payload = 'high'
} else {
msg.payload = 'low'
}
return msg
everything being sent is wrapped in an object called msg
We don't hear this often enough (wanting to learn instead of just copy and pasting ): 
@devifast This is the preferred method of the 2 proposed as it returns the original message & therefore retains any other properties the message needs for processing in downstream nodes.
Did not understand? Maybe you mean that they want ready-made solutions from you? I know how it is with two messages, but here it is about the same message. comparators are something like <=, >=, ==, etc. I don't know them all by heart and that's why I ask people like you. by the way, it doesn't work the way you sent me. the idea is that I just want to describe it in a single line of function. otherwise there is a solution above. Greetings.
You haven't asked for a solution, but instead getting feedback on the attempt/willing to be corrected.
Usually its "Do this please" - so its credit to you.
How can I solve this miracle?
The above in a function node will do what you want (if we have your quest right)
but are you simply trying to compress this into 1 line?
Yes that's right, that's exactly what I'm trying to do right now but to no avail. here is the current code.
var value = msg.payload.current_value;
if(value >= 5)
{
msg.payload = "high";}
else if (value <= 10)
{
msg.payload = "low";
}
else msg.payload = null;
msg.payload = "test";
return msg
[
{
"id": "94220ac1144d4fcb",
"type": "tab",
"label": "Flow 2",
"disabled": false,
"info": "",
"env": []
},
{
"id": "d960b2163cbb35ca",
"type": "inject",
"z": "94220ac1144d4fcb",
"name": "",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "current_value",
"payload": "11",
"payloadType": "num",
"x": 170,
"y": 160,
"wires": [
[
"af617717be62be9e"
]
]
},
{
"id": "3bbc14546fee0417",
"type": "inject",
"z": "94220ac1144d4fcb",
"name": "",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "current_value",
"payload": "7",
"payloadType": "num",
"x": 160,
"y": 110,
"wires": [
[
"af617717be62be9e"
]
]
},
{
"id": "3a370cc26a953786",
"type": "inject",
"z": "94220ac1144d4fcb",
"name": "",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "current_value",
"payload": "4",
"payloadType": "num",
"x": 160,
"y": 220,
"wires": [
[
"af617717be62be9e"
]
]
},
{
"id": "eb423a07871d86f8",
"type": "function",
"z": "94220ac1144d4fcb",
"name": "function 1",
"func": "if(msg.payload.current_value >= 5 && msg.payload.current_value <= 10){\n msg.payload = \"high\"\n} else {\n msg.payload = \"low\"\n}\n\nreturn msg",
"outputs": 1,
"timeout": 0,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 390,
"y": 110,
"wires": [
[
"c6465614c70fb548"
]
]
},
{
"id": "c6465614c70fb548",
"type": "debug",
"z": "94220ac1144d4fcb",
"name": "debug 15",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 500,
"y": 170,
"wires": []
},
{
"id": "85879627632084ef",
"type": "function",
"z": "94220ac1144d4fcb",
"name": "function 2",
"func": "var value = msg.payload.current_value;\nif(value >= 5)\n{\nmsg.payload = \"high\";} \nelse if (value <= 10) \n{\nmsg.payload = \"low\";\n}\nelse msg.payload = null;\nmsg.payload = \"test\";\nreturn msg",
"outputs": 1,
"timeout": 0,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 370,
"y": 250,
"wires": [
[
"a67704c543b711db"
]
]
},
{
"id": "a67704c543b711db",
"type": "debug",
"z": "94220ac1144d4fcb",
"name": "debug 16",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 500,
"y": 260,
"wires": []
},
{
"id": "3701aa908755686b",
"type": "debug",
"z": "94220ac1144d4fcb",
"name": "debug 17",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 490,
"y": 380,
"wires": []
},
{
"id": "af617717be62be9e",
"type": "function",
"z": "94220ac1144d4fcb",
"name": "function 3",
"func": "if(msg.payload.current_value >= 5 && msg.payload.current_value <= 10){\n msg.payload = 'high'\n} else {\n msg.payload = 'low'\n}\n\nreturn msg",
"outputs": 1,
"timeout": 0,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 350,
"y": 380,
"wires": [
[
"3701aa908755686b"
]
]
}
]
still not sure I get 
Ignoring the logic for a minute
you want
line
line
line
to
line
If the value is outside the limits between 5 and 10 false, if it is within these values true.
Lets try..
/* Set Initial value */
let result = false
/* Alter it based on condition */
if(msg.payload.current_value >= 5 && msg.payload.current_value <= 10){
result = true
}
msg.payload = result
return msg
i.e set to true IF ONLY in the range
On one line, something like
msg.payload = (msg.payload >= 5 && msg.payload <= 10);
return msg;
Or
return {payload: (msg.payload >= 5 && msg.payload <= 10)};
it was there the whole time 
Thanks for the elegant solution. That was what it was about.
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