grouptransform
Transform by group
Syntax
Description
Table Data
returns transformed data in the place of the nongrouping variables in table or
timetable G
= grouptransform(T
,groupvars
,method
)T
. The group-wise computations in
method
are applied to each nongrouping variable. Groups
are defined by rows in the variables in groupvars
that have
the same unique combination of values. For example, G =
grouptransform(T,"HealthStatus","norm")
normalizes the data in
T
by health status using the 2-norm.
specifies to bin rows in G
= grouptransform(T
,groupvars
,groupbins
,method
)groupvars
according to binning
scheme groupbins
prior to grouping and appends the bins to
the output table as additional variables. For example, G =
grouptransform(T,"SaleDate","year","rescale")
bins by sale year
and scales the data in T
to the range [0, 1].
specifies additional properties using one or more name-value arguments for any
of the previous syntaxes. For example, G
= grouptransform(___,Name,Value
)G =
grouptransform(T,"Temp","linearfill","ReplaceValues",false)
appends the filled data as an additional variable of T
instead of replacing the nongrouping variables.
Array Data
returns transformed data in the place of column vectors in the input vector or
matrix B
= grouptransform(A
,groupvars
,method
)A
. The group-wise computations in
method
are applied to all column vectors in
A
. Groups are defined by rows in the column vectors in
groupvars
that have the same unique combination of
values.
specifies additional properties using one or more name-value arguments for
either of the previous syntaxes for an input array.B
= grouptransform(___,Name,Value
)
Examples
Input Arguments
Output Arguments
Tips
When making many calls to
grouptransform
, consider converting grouping variables to typecategorical
orlogical
when possible for improved performance. For example, if you have a string array grouping variable (such asHealthStatus
with elements"Poor"
,"Fair"
,"Good"
, and"Excellent"
), you can convert it to a categorical variable using the commandcategorical(HealthStatus)
.
Extended Capabilities
Version History
Introduced in R2018bSee Also
Functions
groupsummary
|groupfilter
|groupcounts
|findgroups
|splitapply
|discretize
|varfun
|rowfun