All -9999 in a table to NaN

Hi Everyone,

I have a table with results from a lot of sensors (1 column per sensor), if the results aren't valid then the output value is -5555.

I want to make all values of -5555 in the entire table =NaN, is there a quick way to do this?

I can do it for 1 column and create a loop to do it for all columns but is there an easier way?

Thanks in advance!

Answer 1

[Steven Lord]

Use standardizeMissing.

dblVar = [NaN;3;Inf;7;9];
cellstrVar = {'one';'three';'';'N/A';'nine'};
charVar = ['A';'C';'E';' ';'I'];
categoryVar = categorical({'red';'yellow';'blue';'violet';''});

A = table(dblVar,cellstrVar,charVar,categoryVar)

A = 5×4 table
    dblVar    cellstrVar    charVar    categoryVar
    ______    __________    _______    ___________

     NaN      {'one'   }       A       red        
       3      {'three' }       C       yellow     
     Inf      {0×0 char}       E       blue       
       7      {'N/A'   }               violet     
       9      {'nine'  }       I       <undefined>

B = standardizeMissing(A, 7)

B = 5×4 table
    dblVar    cellstrVar    charVar    categoryVar
    ______    __________    _______    ___________

     NaN      {'one'   }       A       red        
       3      {'three' }       C       yellow     
     Inf      {0×0 char}       E       blue       
     NaN      {'N/A'   }               violet     
       9      {'nine'  }       I       <undefined>

[Huw Wadkin]

Thanks You! I knew I was missing something simple!

Answer 2

[dpb]

isBad=(T{:,:)==-5555);        % logical array across table T
T{:,:)(isBad)=nan;            % assign NaN to those locations

Use your table variable name in place of T above, of course.

Depending on how you're creating the table, it may be easier/more direct to use the IsMissing indicator when create the table rather than have to fix up after the fact; we would have to know how the table is being populated to begin with to say -- that is, we need to see the code.