A variable falls under the category of "Python identifier". SUch an identifier must start with a letter (uppercase or lowercase) or an underscore, followed by zero or more letters, underscores, and digits. Note that Python is case-sensitive; for example, myvariable, MyVariable, and MYVARIABLE would be treated as three different variables.
XML has no rules like html in regards to tags and naming tags, you write your own xml tags.
The naming convention for variables, constants, classes, and methods involves delimiting separate words with a non-alphanumeric character such as a hyphen or underscore.
Make sure you have the latest version of python downloaded.Run the fileSelect install for all users or install just for me, click NextYou'll see it installs under the C:\Python27 folder, click NextClick Next again for the 'Customize Python' stepClick FinishOpen Control Panel, then SystemClick 'Advanced system settings' on the leftClick the 'Environment Variables' buttonUnder 'System variables' click the variable called 'Path' then the 'Edit...' buttonWithout deleting any other text, add C:\Python27;(include the semi-colon) to the beginning of the 'Variable value' and click OK.Click OK on the 'Environment Variables' window.Restart your computer.Next when you open a command prompt window after the computer restarts and type python you will have python running in the command prompt.
there are various types of naming rule provide for function ,identifier,i.e variables.but naming rule for variable must meet certain condition.. 1.you can easily idenfy what is variable for.for eg.you may use int a;/to store no of student in your prog. but it is better instead of using "a",you can write any of the following definition int stu; or int stu_no; or int studentno; 2.it must be abbreviated.because although modern compiler support 32 char variable but still where you use that variable you have to type that name again &again. so for eg. in the above case int stu_no; is optimal. when these precondition are met then here are some rules for naming a variable: 1.you use only English alphabet,numeric no,& _(underscore). 2.you must start with a alphabet. then you continue with alphabet or numeric or under score.for eg. you can define a variable like int stu_comp_2009;//for no of student 2009 batch. 3.no variable can start with number or _.such naming may cause some compiler do the right job but maximum would not support this.
The same rules apply to naming arrays as for naming any other identifier (be it a user-defined data type, variables or constants and function names). All identifiers must begin with a non-digit character (see below) and must be unambiguous. Global or external identifiers may be subject to additional restrictions as they have to be processed by other software such as linkers. Non-digit characters: _ a b c d e f g h i j k l m n o p q r s t u v w x y z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
The IUPAC rules for naming new chemical elements are at this link.
Upper & Lower case letters are the naming rules on Microsoft Word 2007.
XML has no rules like html in regards to tags and naming tags, you write your own xml tags.
well on land the tiger but in the water the python rules.
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The rules for naming chemical elements and for chemical symbols are established by IUPAC; see this link.
It's just a naming convention. The rules of nomenclature were somewhat arbitrary at first. Then the need of standardization became apparent, and so formal naming rules came into play (sort of).
A standardized system composed of methods rules and guidelines for naming atoms ions and compounds is known as chemical nomenclature
In algebraic equations, exponents can contain variables. They can be solved for by using logarithmic rules for exponents.
You need a book, not an answer here for that question.
Identifiers can be composed from any combination of alphanumeric and underscore characters, but must not begin with a leading digit. Leading underscores are discouraged but allowed. Reserved words cannot be used as keywords.
you cant because variables cant go ou its agaist the rules