removevars

Delete variables from table or timetable

Syntax

T2 = removevars(T1,vars)

Description

T2 = removevars(T1,vars) deletes the table variables specified by vars and copies the remaining variables to T2. You can specify variables by name, by position, or using logical indices.

For example, to remove table variable var3, use T2 = removevars(T1,'var3').

Examples

Remove Variable

Create a table and remove variables one at a time. You can specify variables by name or by position in the table.

Read data from a spreadsheet into a table. Display the first three rows.

T1 = readtable('outages.csv');
head(T1,3)

       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'}

Remove the variable that is named Region.

T2 = removevars(T1,'Region');
head(T2,3)

       OutageTime        Loss     Customers     RestorationTime          Cause      
    ________________    ______    __________    ________________    ________________

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

Remove the fourth variable from T2.

T3 = removevars(T2,4);
head(T3,3)

       OutageTime        Loss     Customers          Cause      
    ________________    ______    __________    ________________

    2002-02-01 12:18    458.98    1.8202e+06    {'winter storm'}
    2003-01-23 00:49    530.14    2.1204e+05    {'winter storm'}
    2003-02-07 21:15     289.4    1.4294e+05    {'winter storm'}

Specify Multiple Variables

Remove multiple table variables using the removevars function. You can specify variables by name or by position.

Read data from a spreadsheet into a table.

T1 = readtable('outages.csv');
head(T1,3)

       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'}

Remove the variables named Loss and Customers. Specify names using a cell array of character vectors.

T2 = removevars(T1,{'Loss','Customers'});
head(T2,3)

       Region           OutageTime       RestorationTime          Cause      
    _____________    ________________    ________________    ________________

    {'SouthWest'}    2002-02-01 12:18    2002-02-07 16:50    {'winter storm'}
    {'SouthEast'}    2003-01-23 00:49                 NaT    {'winter storm'}
    {'SouthEast'}    2003-02-07 21:15    2003-02-17 08:14    {'winter storm'}

Remove the first and fourth variables, using a numeric array to indicate their positions in T2.

T3 = removevars(T2,[1 4]);
head(T3,3)

       OutageTime       RestorationTime 
    ________________    ________________

    2002-02-01 12:18    2002-02-07 16:50
    2003-01-23 00:49                 NaT
    2003-02-07 21:15    2003-02-17 08:14

Input Arguments

T1 — Input table

table | timetable

Input table, specified as a table or timetable.

vars — Variables in input table

string array | character vector | cell array of character vectors | pattern scalar | numeric array | logical array | subscript object

Variables in the input table, specified as a string array, character vector, cell array of character vectors, pattern scalar, numeric array, logical array, or subscript object.

You can specify vars as a subscript object that detects variables of a specified data type by using the vartype function.

Example: T2 = removevars(T1,2) removes the second table variable.

Example: T2 = removevars(T1,'Date') removes the table variable named Date.

Example: T2 = removevars(T1,{'Latitude','Longitude','Elevation'}) removes the table variables named Latitude, Longitude, and Elevation.

Example: vars = vartype('numeric'); T = removevars(T,vars) removes all of the numeric variables in T.

Extended Capabilities

Tall Arrays

Calculate with arrays that have more rows than fit in memory.

The removevars function fully supports tall arrays. For more information, see Tall Arrays.

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

• The vars input argument does not support pattern expressions.

Thread-Based Environment

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

This function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Distributed Arrays

Partition large arrays across the combined memory of your cluster using Parallel Computing Toolbox™.

This function fully supports distributed arrays. For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).

Version History

Introduced in R2018a