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# What does "levelspec" mean in the documentationdo brackets around a levelspec option do?

Post Closed as "off-topic" by Kuba, m_goldberg, Artes, Oleksandr R., Yves Klett
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# Problem with the argument of What does "levelspec" mean in the Cases[] functiondocumentation?

The following code returns the first three integer elements of Sqrt[Range[100]]:

Cases[Sqrt[Range[100]], _Integer, 2, 3]
{1, 2, 3}


The following code looks like the preceding code but returns a different result:

Cases[Sqrt[Range[100]], _Integer, {2}, 3]
{2, 3, 5}


As we can see in the following picture, the argument {2} is not documented (it has no braces in the documentation):

What does the second code with {2} instead of 2 mean?

# Problem with the argument of the Cases[] function

The following code returns the first three integer elements of Sqrt[Range[100]]:

Cases[Sqrt[Range[100]], _Integer, 2, 3]
{1, 2, 3}


The following code looks like the preceding code but returns a different result:

Cases[Sqrt[Range[100]], _Integer, {2}, 3]
{2, 3, 5}


As we can see in the following picture, the argument {2} is not documented (it has no braces in the documentation):

What does the second code with {2} instead of 2 mean?

# What does "levelspec" mean in the documentation?

The following code returns the first three integer elements of Sqrt[Range[100]]:

Cases[Sqrt[Range[100]], _Integer, 2, 3]
{1, 2, 3}


The following code looks like the preceding code but returns a different result:

Cases[Sqrt[Range[100]], _Integer, {2}, 3]
{2, 3, 5}


As we can see in the following picture, the argument {2} is not documented (it has no braces in the documentation):

What does the second code with {2} instead of 2 mean?

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