http://purl.org/tcl/home/man/tcl8.4/TkCmd/radiobutton.htm

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'''Example:'''

Radio buttons are linked using a common variable, which will have the value of the selected button.

 pack [radiobutton .one   -value 1 -text "One"   -variable onetwothree]
 pack [radiobutton .two   -value 2 -text "Two"   -variable onetwothree]
 pack [radiobutton .three -value 3 -text "Three" -variable onetwothree]

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See the ''vertical'' command, which allows to place the text below the checkfield, on the [checkbutton] page.

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