Begin
 Usage
• Begin["context`"] 重设当前上下文。
Notes
• Begin["context`"] 重设当前上下文的值。
• 当前上符号名的解释与上下文有关。这样Begin影响输入表达式的分析。 • 参见 Mathematica 全书: 节 2.6.10.
 Further Examples
This is the current context when you start Mathematica.
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This is the current context path. A symbol whose context name is not specified is looked up first in the current context, then in the contexts in $ContextPath.
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This command changes the current context, but not the context path.
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The following symbol does not exist either in the current context Temporary`, or in the contexts in $ContextPath. As a result, it is created in the current context.
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This is its full name.
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 Following this command, the earlier context is restored.
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Now newsymbol is not recognized, since the context it belongs to is not in the search path.
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A very common use of Begin is to hide symbols defined in packages. This technique is illustrated in the Further Examples for BeginPackage.
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