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isKey

Determine if Map object contains key

Description

example

Note

dictionary is recommended over containers.Map because it accepts more data types as keys and values and provides better performance. (since R2022b)

TF = isKey(M,keySet) returns 1 (true) if M contains the specified key, and returns 0 (false) otherwise.

If keySet is an array that specifies multiple keys, then TF is a logical array of the same size.

Examples

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Create a Map object containing several key-value pairs.

months = {'Jan','Feb','Mar','Apr'};
rainfall = [327.2 368.2 197.6 178.4];
M = containers.Map(months,rainfall)
M = 
  Map with properties:

        Count: 4
      KeyType: char
    ValueType: double

Determine whether m has 'Feb' as a key.

TF = isKey(M,'Feb')
TF = logical
   1

Search for multiple keys.

keySet = {'Mar','Apr','May','Jun'};
TF = isKey(M,keySet)
TF = 1x4 logical array

   1   1   0   0

Input Arguments

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Input Map object.

Keys to search for in the Map object, specified as a numeric scalar, character vector, string scalar, or cell array. To search for multiple keys, specify keySet as a cell array—even when you specify keys as numeric scalars or strings.

Version History

Introduced in R2008b