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| 42.The following SAS program is submitted: data WORK.ONE; Text='Australia, US, Denmark'; Pos=find(Text,'US','i',5); run; What value will SAS assign to Pos? A. 0 B. 1 C. 2 D. 12 Answer: D 本文属于博客：http://www.crackman.net/版权归作者所有，欢迎转载！如有转载，请务必注明出处！未经本文作者同意不得用于商业应用。 本题考察的是SAS中FIND函数的应用。 POS=FIND(Text,'US','i',5)解释为： 从Australia, US, Denmark 字符串的第五个字符开始，忽略字符串中大小写，寻找字符串US在源字符串中的起始位置，并返回起始位置的数字给POS。 几个问题值得思考，第一个是如果没有'i'这个参数，结果会怎么样？如果把5改成1，那么结果又如何？ 看看SAS官网网站的解释： Syntax FIND(string,substring<,modifiers><,startpos>) FIND(string,substring<,startpos><,modifiers>) Searches for a specific substring of characters within a character string. Arguments string specifies a character constant, variable, or expression that will be searched for substrings. Tip: Enclose a literal string of characters in quotation marks. substring is a character constant, variable, or expression that specifies the substring of characters to search for in string. Tip: Enclose a literal string of characters in quotation marks. modifiers is a character constant, variable, or expression that specifies one or more modifiers. The following modifiers can be in uppercase or lowercase: i ignores character case during the search. If this modifier is not specified, FIND only searches for character substrings with the same case as the characters in substring. t trims trailing blanks from string and substring. Note: If you want to remove trailing blanks from only one character argument instead of both (or all) character arguments, use the TRIM function instead of the FIND function with the T modifier. Tip: If modifier is a constant, enclose it in quotation marks. Specify multiple constants in a single set of quotation marks. Modifier can also be expressed as a variable or an expression. startpos is a numeric constant, variable, or expression with an integer value that specifies the position at which the search should start and the direction of the search. |
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