Hello All,
I have a problem.Duhhh 
I want to read-out a DHT22, that works and i am getting the string with tempurature and humidity.
I can filter the values in 2 seperate payloads.
But..
How can i adjust the decimals.
example:
DHT22 -> 27.30 celcius
-> 53.00 humidity
change it in:
DHT22 -> 27.3c
-> 53
Thanks for you help,
Colin
If you want to do that in order to display it in the dashboard then the dashboard nodes have the ability to set the number of decimal places by configuring the Value Format field. This is explained in the Gauge node info tab, I don't know about the others. So to specify one decimal place use {{value | number:1}}
If that is not why you want to do it can you explain the reason. It is usually best to keep all the precision you have till you want to display it.
It is diplayed in the clock.
my flow
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$(\".Clock-Wrapper\").css('background-color', '#bbbb44'); $(\".lcdClock\").css('color', '#222'); } \n if (msg.colour==\"white\") { $(\".Clock-Wrapper\").css('background-color', '#aaaaaa'); $(\".lcdClock\").css('color', '#222'); } \n if (msg.colour==\"pink\") { $(\".Clock-Wrapper\").css('background-color', '#ff8888'); $(\".lcdClock\").css('color', '#222'); } \n if (msg.colour==\"red\") { $(\".Clock-Wrapper\").css('background-color', '#aa2222'); $(\".lcdClock\").css('color', '#ccaa22'); } \n }\n });\n })(scope);\n\n function genTimerStrings(tm, num){\n \n \tvar i;\n \tvar ret = tm.toString(10);\n \tvar left = ret.length;\n \n \tif( left < num){\n \t\tfor(i=0; i<( num - left ); i++ ){\n \t\t\tret = String(0) + ret;\n \t\t}\n \t}\n \treturn ret;\n }\n\n function updateTimer(){\n \tvar ret;\n \tvar date = new Date();\n \tvar tm_year, tm_mon, tm_date, tm_hour, tm_min, tm_sec, tm_msec,tm_day;\n \tvar colon;\n \ttm_year = date.getFullYear();\n \ttm_mon = date.getMonth()+1;\n \ttm_date = date.getDate();\n \ttm_day = date.getDay();\n \ttm_hour = date.getHours();\n \ttm_min = date.getMinutes();\n \ttm_sec = date.getSeconds();\n \ttm_msec = date.getMilliseconds();\n \n \ttm_mon = genTimerStrings(tm_mon, 2);\n \ttm_date = genTimerStrings(tm_date, 2);\n \ttm_hour = genTimerStrings(tm_hour, 2);\n \ttm_min = genTimerStrings(tm_min, 2);\n \ttm_sec = genTimerStrings(tm_sec, 2);\n \ttm_day = daylist[tm_day];\n \n \tif( tm_msec > 499 ){\n \t\tcolon = ' ';\n \t}else{\n \t\tcolon = ':';\n \t}\n \n \tdocument.getElementById(\"DSEGClock\").innerHTML = tm_hour + colon + tm_min + \"<span style=\\\"font-size:30px;\\\">\" + tm_sec + \"</span>\";\n \tdocument.getElementById(\"DSEGClock-Year\").innerHTML = \"<span class=\\\"D7MI\\\">\" + tm_year + \"-\" + tm_mon + \"-\" + tm_date + ' ' + \"</span><span class=\\\"D14MI\\\">\" + tm_day + \".\" + \"</span>\";\n \n \tsetTimeout(\"updateTimer()\", 500 - date.getMilliseconds()%500 );\n }\n\n updateTimer();\n</script>\n\n<style 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\"DWEATHER\";\nfont-size:72px;\nheight:72px;\n}\n\n.Clock-Wrapper{\n\tposition:relative;\n\tborder:6px solid #000;\n\tborder-radius:9px;\n\theight:68px;\n\twidth:280px;\n\tbackground-color:#fb7c00;\n\tbackground-color:#000000;\n\n\tbox-shadow: 4px 4px 28px 0px rgba(0,0,0,0.3) inset;\n\t-moz-transform: scale(2.52); /* for Firefox, default 1*/\nzoom:252%; /* For Chrome, IE, default 100%*/\n}\n\n.Clock-Time-Background{\n\tz-index:50;\n\tcolor:rgba(0,0,0,0.15);\n}\n\n.Clock-Time-Front{\n\tz-index:100;\n}\n\n.Clock-Time-Background,.Clock-Time-Front {\n \tposition:absolute;\n\ttop:38px;\n\tleft:5px; \n\tfont-size:42px;\n}\n\n.Clock-Year-Background{\n\tz-index:50;\n;\n\tcolor:rgba(0,0,0,0.1);\n\tfont-size:18px;\n}\n\n.Clock-Year-Front{\n\tz-index:100;\n}\n\n.Clock-Year-Background,.Clock-Year-Front {\n \tposition:absolute;\n\ttop:2px;\n\tleft:5px; \n\tfont-size:18px;\n}\n\n.temp { z-index:100; }\n.tempBack { z-index:50; color:rgba(0,0,0,0.1); }\n.temp,.tempBack {\n \tposition:absolute;\n\ttop:28px;\n\tleft:210px; \n\tfont-size:18px;\n}\n\n.tempc { z-index:100; }\n.tempcBack { z-index:50; color:rgba(0,0,0,0.1); }\n.tempc,.tempcBack {\n \tposition:absolute;\n\ttop:36px;\n\tleft:278px; \n\tfont-size:24px;\n}\n\n#DSEG7_OUTPUT{\n\tfont-family: \"D7MI\";\n}\n\n#DSEG14_OUTPUT{\n\tfont-family: \"D14MI\";\n}\n\n#DSEG14_OUTPUT, #DSEG7_OUTPUT{\n\tfont-size:18px;\n\tmargin-top:2px;\n\tmargin-bottom:10px;\n}\n\n</style>\n\n\n<div class=\"Clock-Wrapper center lcdClock\">\n\t<span class=\"Clock-Time-Background D7MBI\">88:88<span style=\"font-size:30px;\">88</span></span>\n\t<span id=\"DSEGClock\" class=\"Clock-Time-Front D7MBI\"></span>\n\t<span class=\"Clock-Year-Background\"><span class=\"D7MI\">2088-88-88</span><span class=\"D14MI\"> ~~~</span></span>\n\t<span id=\"DSEGClock-Year\" class=\"Clock-Year-Front\"></span>\n\t\n\t<span id=\"DSEGTemp\" class=\"temp D7MBI\">41</span>\n\t<span id=\"DSEGTemp\" class=\"tempBack D7MBI\">88</span>\t\n\t<span id=\"DSEGTempc\" class=\"tempc D7MI\">C</span>\n\t<span id=\"DSEGTempc\" class=\"tempcBack D7MI\">8</span>\t\n</div>\n\n","storeOutMessages":true,"fwdInMessages":false,"resendOnRefresh":false,"templateScope":"local","x":360,"y":260,"wires":[[]]},{"id":"e796e59c.744638","type":"inject","z":"6bc50f94.1dba4","name":"21c","topic":"","payload":"21","payloadType":"num","repeat":"","crontab":"","once":false,"x":150,"y":241,"wires":[["4c49dd26.cee034"]]},{"id":"5a75cabc.dd548c","type":"inject","z":"6bc50f94.1dba4","name":"32c","topic":"","payload":"32","payloadType":"num","repeat":"","crontab":"","once":false,"x":150,"y":281,"wires":[["4c49dd26.cee034"]]},{"id":"25c161.b26d26a","type":"inject","z":"6bc50f94.1dba4","name":"green","topic":"","payload":"green","payloadType":"str","repeat":"","crontab":"","once":false,"x":150,"y":340,"wires":[["f9c1154a.88a4b8"]]},{"id":"4885793e.0d1cd","type":"inject","z":"6bc50f94.1dba4","name":"orange","topic":"","payload":"orange","payloadType":"str","repeat":"","crontab":"","once":false,"x":150,"y":380,"wires":[["f9c1154a.88a4b8"]]},{"id":"f9c1154a.88a4b8","type":"function","z":"6bc50f94.1dba4","name":"","func":"msg.colour=msg.payload;\nmsg.payload=undefined;\nreturn 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In javascript you can use toFixed() to do it.
could you give me an example?
for temperature i use:
msg.payload = msg.payload
return msg;
https://www.w3schools.com/jsref/jsref_tofixed.asp
This will only work if your temp is a number i.e. 27.30.
But if as i suspect your value is a string i.e. "27.30 celcius".
Then you will need to convert your string.
https://www.w3schools.com/jsref/jsref_number.asp
https://www.w3schools.com/jsref/jsref_split.asp
i do not understand.
could you look into my flow and edit the functions after the dht22?
What is the output of the debug, as until i am sure of the format, i can not know how to convert it
num.toFixed(2); the example from the link i provided
num would be your variable msg.payload, if it is a number.
If msg.payload is a string it will not work.
Hi there,
I'm using a DHT22 and this is what I'm doing
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I've then got a couple of Function nodes to turn the string value into a number
msg.payload = parseFloat(msg.payload);
return msg;
The nugget you probably need is the Math.round() function
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/round
I use it to round to two decimal places
var x = parseFloat(str);
x = Math.round(x*100)/100;
msg.payload = x
return msg;
Hope this helps.
Rather than using round you can use toFixed() which is a little simpler.
var x = parseFloat(str);
msg.payload = x.toFixed(2)
return msg;
Nice one, much cleaner.
this is what the dht22 is sending
{"_msgid":"4b5035d7.5cecdc","topic":"rpi-dht22","payload":"23.90","humidity":"58.80","isValid":true,"errors":0,"sensorid":"dht22"}
when i use toFixed or Math solutions i am getting errors like:
I think you are missing this line at the start of your function block.
var str = msg.payload;
No sorry this is what I'm using after passing the info to another Rpi to spit what is a string out into numbers. it's the Str>Num Function
Guy, super thanks!
my first funcyion after DHT22 is:
msg.payload = msg.payload;
return msg;
The second function is:
var str = msg.payload;
var x = parseFloat(str);
msg.payload = x.toFixed(1)
return msg;
and this gives me the temperature with 1 decimal.
Your first function does absolutely nothing (other than consume a bit of processor time). You don't need it.
When people post flows for you to use please make sure that you understand what they are doing. That way you learn much more. If you don't understand something then ask.
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