Select elements that are even:

Return the indices of the selected elements:

Return only the first expression selected:

Use the operator form of Select :

Select operates on values in an Association :

Select rows in a Tabular object:

Select numbers up to 100 that equal 1 modulo both 3 and 5:

Select 4-tuples that read the same in reverse:

Find the first four 3×3 matrices of 0s and 1s that have determinant 1:

Select eigenvalues that lie within the unit circle:

Find built-in Wolfram Language objects whose names are less than 3 characters long:

Select numeric quantities from a product:

Find an approximation to by finding the proportion of points that lie within a disk:

Select is complementary to Discard :

Select is similar to Cases except that it uses a function instead of a pattern:

Select the lists that have sum of elements less than 10:

Use Cases to get the same result:

Select elements that are even:

Use GatherBy to separate odd and even elements:

Use GroupBy to construct an association explicitly containing as keys the results of the criterion:

Compute Select in parallel:

Select picks out elements for which applying the criterion explicitly yields True :

The symbolic object x is not included in either case, since neither inequality gives True :

The head of the input expression is only preserved for the default "Element" property: