Palindromes

A palindrome is a number, word, or sentence that reads the same from left to right and right to left. Use PalindromeQ, its options, and other string-related low-level functions to test for palindromic words and sentences.

This is an English palindrome.

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PalindromeQ["racecar"]

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The name Anna is also a palindrome, but you need to ignore the capitalization.

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PalindromeQ["Anna", IgnoreCase -> True]

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Use Decapitalize as an alternative to make the first character be lowercase.

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PalindromeQ[Decapitalize["Anna"]]

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The French verb "rêver" is a palindrome as well, but you need to ignore the diacritic.

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PalindromeQ["rêver", IgnoreDiacritics -> True]

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Use RemoveDiacritics to process the verb instead.

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PalindromeQ[RemoveDiacritics["rêver"]]

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With palindromic sentences, you also generally need to process the initial string.

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sentence = "Now, sir, a war is won!";

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PalindromeQ[sentence]

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StringDelete[sentence, PunctuationCharacter | Whitespace]

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StringDelete[sentence, PunctuationCharacter | Whitespace]; PalindromeQ[%, IgnoreCase -> True]

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