Fill Unknown data with mode in matlab

Question

Let us suppose we have following matlab code which reads csv file, converts text data to the categorical form and prints data :

data =readtable("fruit_data.csv");
data.fruit_name =categorical(data.fruit_name);
data.fruit_subtype=categorical(data.fruit_subtype);
head(data)





8×7 table

    fruit_label    fruit_name    fruit_subtype    mass    width    height    color_score
    ___________    __________    _____________    ____    _____    ______    ___________

         1          apple        granny_smith     192      8.4      7.3         0.55    
         1          apple        granny_smith     180        8      6.8         0.59    
         1          apple        granny_smith     176      7.4      7.2          0.6    
         2          mandarin     mandarin          86      6.2      4.7          0.8    
         2          mandarin     mandarin          84        6      4.6         0.79    
         2          mandarin     mandarin          80      5.8      4.3         0.77    
         2          mandarin     mandarin          80      5.9      4.3         0.81    
         2          mandarin     mandarin          76      5.8        4         0.81    
tail(data)

we get : ans =

 8×7 table

    fruit_label    fruit_name    fruit_subtype    mass    width    height    color_score
    ___________    __________    _____________    ____    _____    ______    ___________

         4           lemon          unknown       116        6      7.5         0.72    
         4           lemon          unknown       118      5.9        8         0.72    
         4           lemon          unknown       120        6      8.4         0.74    
         4           lemon          unknown       116      6.1      8.5         0.71    
         4           lemon          unknown       116      6.3      7.7         0.72    
         4           lemon          unknown       116      5.9      8.1         0.73    
         4           lemon          unknown       152      6.5      8.5         0.72    
         4           lemon          unknown       118      6.1      8.1          0.7  

i want to fill unknown data with the most frequent element (so called mode), like in pandas, i can select only those rows that contains unknown

data(data.fruit_subtype=='unknown',:) 


10×7 table

    fruit_label    fruit_name    fruit_subtype    mass    width    height    color_score
    ___________    __________    _____________    ____    _____    ______    ___________

         4           lemon          unknown       132      5.8      8.7         0.73    
         4           lemon          unknown       130        6      8.2         0.71    
         4           lemon          unknown       116        6      7.5         0.72    
         4           lemon          unknown       118      5.9        8         0.72    
         4           lemon          unknown       120        6      8.4         0.74    
         4           lemon          unknown       116      6.1      8.5         0.71    
         4           lemon          unknown       116      6.3      7.7         0.72    
         4           lemon          unknown       116      5.9      8.1         0.73    
         4           lemon          unknown       152      6.5      8.5         0.72    
         4           lemon          unknown       118      6.1      8.1          0.7    
 but when i am writing following code :
data(data.fruit_subtype=='unknown',:) =mode(data.fruit_subtype)

result is :

Right hand side of an assignment into a table must be another table or a cell array.

i have tried following

data(data.fruit_subtype=='unknown',:) =cell(mode(data.fruit_subtype))

but i have got :

Error using cell
Conversion to cell from categorical is not possible.

please help me how to fix it?