struct2table

Convert structure array to table

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Syntax

T = struct2table(S)
T = struct2table(S,Name,Value)

Description

T = struct2table(S) converts a structure array to a table. Each field of the input structure becomes a variable in the output table.

  • If the input is a scalar structure with n fields, all of which have m rows, then the output is an m-by-n table.

  • If the input is an m-by-1 or 1-by-m structure array with n fields, then the output is an m-by-n table.

example

T = struct2table(S,Name,Value) creates a table from a structure array, with additional options specified by one or more Name,Value arguments.

For example, you can specify row names to include in the table.

example

Examples

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Open Live Script

Convert a scalar structure to a table using the default options.

Create a structure array, S. 

S.Name = ["Chang";"Brown";"Ruiz"];
S.Smoker = ["Y";"N";"Y"];
S.SystolicBP = [124;122;130];
S.DiastolicBP = [93;80;92];

The scalar structure, S, has four fields, each with three rows.

Convert the structure array to a table. 

T = struct2table(S)
T=3×4 table
     Name      Smoker    SystolicBP    DiastolicBP
    _______    ______    __________    ___________

    "Chang"     "Y"         124            93     
    "Brown"     "N"         122            80     
    "Ruiz"      "Y"         130            92

The structure field names in S become the variable names in the output table. The size of T is 3-by-4.

Change Name from a variable to row names by modifying the table property, T.Properties.RowNames, and then deleting the variable Name. 

T.Properties.RowNames = T.Name;
T.Name = [];

T
T=3×3 table
             Smoker    SystolicBP    DiastolicBP
             ______    __________    ___________

    Chang     "Y"         124            93     
    Brown     "N"         122            80     
    Ruiz      "Y"         130            92
Open Live Script

Create a nonscalar structure array, S. 

S(1,1).Name = "Chang";
S(1,1).Smoker = "Y";
S(1,1).SystolicBP = 124;
S(1,1).DiastolicBP = 93;

S(2,1).Name = "Brown";
S(2,1).Smoker = "N";
S(2,1).SystolicBP = 122;
S(2,1).DiastolicBP = 80;

S(3,1).Name = "Ruiz";
S(3,1).Smoker = "Y";
S(3,1).SystolicBP = 130;
S(3,1).DiastolicBP = 92;

S
S=3×1 struct array with fields:
    Name
    Smoker
    SystolicBP
    DiastolicBP

S is a 3-by-1 structure array with four fields.

Convert the structure array to a table. 

T = struct2table(S)
T=3×4 table
     Name      Smoker    SystolicBP    DiastolicBP
    _______    ______    __________    ___________

    "Chang"     "Y"         124            93     
    "Brown"     "N"         122            80     
    "Ruiz"      "Y"         130            92

The structure field names in S become the variable names in the output table. The size of T is 3-by-4.

Open Live Script

Use "AsArray",true to create a table from a scalar structure whose fields have different numbers of rows.

Create a scalar structure, S, with fields name, billing, and test. 

S.name = "John Doe";
S.billing = 127.00;
S.test = [79, 75, 73; 180, 178, 177.5; 220, 210, 205]
S = struct with fields:
       name: "John Doe"
    billing: 127
       test: [3×3 double]

The fields have different numbers of rows. Therefore, you cannot use struct2table(S), which uses "AsArray",false by default.

Treat the scalar structure as an array and convert it to a table. 

T = struct2table(S,"AsArray",true)
T=1×3 table
       name       billing        test    
    __________    _______    ____________

    "John Doe"      127      {3×3 double}

T contains one row.

Input Arguments

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Input array, specified as a structure.

Name-Value Arguments

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Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: "RowNames",["row1","row2","row3"] uses the row names, row1, row2, and row3 for the table, T.

Row names, specified as a cell array of character vectors or string array, whose elements are nonempty and distinct. The number of row names must equal the number of rows of the input array.

Row names can have any Unicode® characters, including spaces and non-ASCII characters, except for ':'.

If you specify row names that have leading or trailing whitespace characters, then struct2table removes them from the row names.

Since R2021a

Dimension names, specified as a two-element cell array of character vectors or two-element string array whose elements are nonempty and distinct.

Dimension names can have any Unicode characters, including spaces and non-ASCII characters. However, a dimension name cannot match any table variable name or the reserved names 'Properties', 'RowNames', 'VariableNames', or ':'.

As an alternative, in all releases you can specify dimension names by setting the DimensionNames property of the table.

Flag to treat the input as a structure array, specified as a numeric or logical 1 (true) or 0 (false).

true

Default if input is nonscalar structure array

Converts structure array to a table with one row for each structure and one variable for each field of the structure array. The fields can have different sizes.

If the values in field S(1:m).fieldname have:

  • Compatible sizes and data types, and each value has one row, then the corresponding table variable is a homogeneous array.

    Example:

    S(1).a = [1 2]
S(2).a = [3 4]
S(1).b = 5
S(2).b = 6
T = struct2table(S)

    T =
  2×2 table
      a       b
    ______    _
    1    2    5
    3    4    6

  • Different sizes, incompatible data types, or any value has more than one row, then the corresponding table variable is a cell array.

    Example:

    S(1).a = [1 2]
S(2).a = [3 4 5 6]
S(1).b = 7
S(2).b = 8
T = struct2table(S)

    T =
  2×2 table
         a         b
    ___________    _
    {[    1 2]}    7
    {[3 4 5 6]}    8

false

Default if input is scalar structure

Converts a scalar structure with n fields into an m-by-n table. Each field must have m rows.

Example:

S.a = [1;2;3]
S.b = [4 5;6 7;8 9]
T = struct2table(S)

T =
  3×2 table
    a      b   
    _    ______
    1    4    5
    2    6    7
    3    8    9

Output Arguments

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Output table, returned as a table. The table can store metadata such as descriptions, variable units, variable names, and row names. For more information, see the Properties section of table.

Extended Capabilities

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Thread-Based Environment
Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

Version History

Introduced in R2013b

See Also

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