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head

Get top rows of array or table

Description

example

head(A) displays the first eight rows of array, table, or timetable A in the Command Window without storing a value.

example

head(A,k) displays the first k rows of A.

example

B = head(___) returns the requested rows of A for either of the previous syntaxes. The data type of B is the same as the data type of A.

Examples

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Create a matrix with 100 rows, and display the first eight rows of the matrix.

If you do not specify an output argument, head does not return a value. It only displays the top of the matrix.

A = repmat((1:100)',1,4);
head(A)
     1     1     1     1
     2     2     2     2
     3     3     3     3
     4     4     4     4
     5     5     5     5
     6     6     6     6
     7     7     7     7
     8     8     8     8

Create a table from a file with 1468 rows.

T = readtable("outages.csv","TextType","string");
size(T)
ans = 1×2

        1468           6

Display the first three rows. If you do not specify an output argument, head does not return a value. It only displays the top of the table.

head(T,3)
      Region          OutageTime        Loss     Customers     RestorationTime         Cause     
    ___________    ________________    ______    __________    ________________    ______________

    "SouthWest"    2002-02-01 12:18    458.98    1.8202e+06    2002-02-07 16:50    "winter storm"
    "SouthEast"    2003-01-23 00:49    530.14    2.1204e+05                 NaT    "winter storm"
    "SouthEast"    2003-02-07 21:15     289.4    1.4294e+05    2003-02-17 08:14    "winter storm"

Create a table by reading data from a spreadsheet. Display the size of the table, showing that it has 1468 rows.

T = readtable("outages.csv","TextType","string");
size(T)
ans = 1×2

        1468           6

Return another table that has the first eight rows of T.

T2 = head(T)
T2=8×6 table
      Region          OutageTime        Loss     Customers     RestorationTime           Cause      
    ___________    ________________    ______    __________    ________________    _________________

    "SouthWest"    2002-02-01 12:18    458.98    1.8202e+06    2002-02-07 16:50    "winter storm"   
    "SouthEast"    2003-01-23 00:49    530.14    2.1204e+05                 NaT    "winter storm"   
    "SouthEast"    2003-02-07 21:15     289.4    1.4294e+05    2003-02-17 08:14    "winter storm"   
    "West"         2004-04-06 05:44    434.81    3.4037e+05    2004-04-06 06:10    "equipment fault"
    "MidWest"      2002-03-16 06:18    186.44    2.1275e+05    2002-03-18 23:23    "severe storm"   
    "West"         2003-06-18 02:49         0             0    2003-06-18 10:54    "attack"         
    "West"         2004-06-20 14:39    231.29           NaN    2004-06-20 19:16    "equipment fault"
    "West"         2002-06-06 19:28    311.86           NaN    2002-06-07 00:51    "equipment fault"

Input Arguments

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Input data, specified as an array, cell array, table, or timetable.

Number of rows to extract, specified as a positive integer. If A has fewer than k rows, then head returns all rows of A.

Extended Capabilities

Version History

Introduced in R2016b

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