table

Methods

⌂ table

Method Reference: table.standardizeMissing

table: tblB = standardizeMissing (tblA, indicator)

table: tblB = standardizeMissing (…, Name, Value)

Insert standard missing values into a table.

tblB = standardizeMissing (tblA, indicator) replaces every entry of tblA that matches a value in indicator with the standard missing value of that variable’s data type (NaN for double/single and duration, '' for cell arrays of character vectors, <missing> for string, <undefined> for categorical, and NaT for datetime).

indicator may be a numeric scalar or vector, a character vector, a string array, a cell array of character vectors, a duration or datetime array, or a cell array mixing any of these. Each indicator is applied only to the variables whose type is compatible with it: numeric indicators match double and single variables, text indicators (char, string, or cellstr) match cell-array-of-character-vector, string, and categorical variables, duration indicators match duration variables, and datetime indicators match datetime variables. A datetime indicator matches the same instant in any time zone, but indicators with and without a time zone cannot be mixed, nor compared with a variable that differs from them in having one.

The 'DataVariables' Name/Value pair restricts the operation to a subset of variables, using the same variable referencing as the other table methods. Variables not selected pass through unchanged.

Logical and integer variables (which have no standard missing value) and calendarDuration variables pass through unchanged.

Source Code: table

standardizeMissing turns your own sentinel codes into the standard missing value for each type (NaN here), so later ismissing/rmmissing/ fillmissing calls recognise them. This dataset uses -99 for "no data".

 T = table ([38; -99; 40], [71; 69; -99], 'VariableNames', {'Age', 'Height'})
T =
  3x2 table

    Age    Height    
    ___    ______    

     38        71    
    -99        69    
     40       -99
 S = standardizeMissing (T, -99)
S =
  3x2 table

    Age    Height    
    ___    ______    

     38        71    
    NaN        69    
     40       NaN

The sentinels are now genuine missing values, ready to be filled or dropped.

 rmmissing (S)
ans =
  1x2 table

    Age    Height    
    ___    ______    

     38        71