Data comparison and storing

I've created a sensor to take readings daily .

Humidity = 

  20×1 string array

    "34.099045"
    "42.425098"
    "33.480418"
    "35.790796"
    "30.370059"
    "44.029928"
    "49.041827"
    "44.980187"
    "45.134548"
    "40.841782"
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>
    <missing>


HumidityTime =

     2    24
     4    48
     7    12
     9    36
    12     0
    14    24
    16    48
    19    12
    21    36
    24     0

[Peng Li]

You question isn’t clear. Without hardcoded value, did you mean that you want to find values between the two numbers you gave?

You humidity time has 10 rows while humidity has 20, it isn’t clear how to match them.

You may want to first convert the humidity string to double using str2double. It will then easier for you to make any math calc.

[Walter Roberson]

In the special case of string object array, which we can see is present here, then you can use double() instead of str2double()

[Zeus]

hi thanks ,i realised i made a mistake there

so im supposed to just write the code without checking the data(just call it as it always changes)

i need to store only the values that exceed the threshold and the corresponding times these values are taken at in a ? ×3 vector

so far ive got this :

I may be wrong for using else .

SensorData
Humidity;
HumidityTime;
HumidityAlert= []
n=1
for i= 1:1:length(Humidity)
    if (40< Humitiy)&& (Humidity<50)
        %something is missing here
    else HumidityAlert= [] %not sure if this is correct
    end
end

[Peng Li]

Again you have 20 rows in humidity data but 10 rows in humidity time. How do they match? If they match by rows, you can use HumidityTime(double(humidity) > 40 & double(humidity) < 50, :) to get the times that humidity meet your defined criterion.

[Zeus]

so i managed to get them to be equal ,I got rid of the excess <missing> terms by changing my data collection code.

I have tried ur suggestion HumidityTime(double(humidity) > 40 & double(humidity) < 50 and it is not working .Please suggest an alternative

Humidity =

   46.8068
   42.5006
   35.1041
   48.0938
   45.3460
   41.2533
   47.9431
   37.3616
   36.7546
   42.3771


HumidityTime =

     2    24
     4    48
     7    12
     9    36
    12     0
    14    24
    16    48
    19    12
    21    36
    24     0

Answer 1

[Mohammad Sami]

Humidity = str2double(Humidity(~ismissing(Humiditiy)));
lowlimit = 40;
highlimit = 50;
outsidelimit = Humidity > highlimit || Humidity < lowlimit;
alerts = [HumidityTime(outsidelimit,:) Humidity(outsidelimit)];

[Zeus]

it gives me this when i run .i need to have nx3 matrix in output (hours minutes Humidity)

Humidity =

   NaN


outsidelimit =

  logical

   0


alerts =

  0×2 empty double matrix
  
  

[Walter Roberson]

At the time you get that output, what is the string array that you are starting with ?