The following operators are available for strings:<\/p>\n
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- [] – index operator.<\/li>\n
- [:] \u00a0– slicing<\/li>\n
- \u00a0+ adding<\/li>\n<\/ol>\n
We will look at the above in more detail.<\/p>\n
[] – index operator<\/strong><\/p>\n
As mentioned before, strings are collections of characters. So to access individual characters in a string we use the index operator. The lowest index value is zero which represents the first character and the highest index value is the length of the string minus one.<\/p>\n
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As you can see above print name[13] gives an error since the length of the string is 12. For an empty string blank = ” the length of the string is zero, so print blank[0] gives an error.<\/p>\n
[:] slicing<\/strong><\/p>\n
The index operator lets you extract one character from the string. The slicing operator lets us extract multiple characters from a string. The operator takes two numbers [x:y] where x is the starting index and y is the ending index. Note that the ending index is not inclusive eg. if you try print name[1:3] it will extract character at index 1 and then stop at index 2.<\/p>\n
The slicing operator has various permutations and combinations as shown below:<\/p>\n
- \n
- [x:y] – extract from x and stop before y<\/li>\n
- [x:] – extract from x till the rest of the string<\/li>\n
- [:y] – extract from the first character till y<\/li>\n
- [-x:] – extract x characters from the end<\/li>\n
- [:-y] – extract from the first character and stop before y<\/li>\n
- [:] – no x and y . Extract the whole string<\/li>\n<\/ul>\n
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+ adding<\/strong><\/p>\n
Adding two strings together gives a new third string. Examples are shown below:<\/p>\n
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Methods<\/h3>\n
Methods are functions which are available for string variables. The following methods are available:<\/p>\n
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- lower() – convert string to lowercase<\/li>\n
- upper() – convert string to uppercase<\/li>\n
- strip() \u00a0– remove any leading or trailing spaces in the string<\/li>\n
- isalpha() – check if all characters in string are alphabets<\/li>\n
- isdigit() – check if all characters in string are digits<\/li>\n
- isspace() – check if all characters in string are spaces<\/li>\n
- startswith(x) – check if string starts with the string specified by x<\/li>\n
- endswith(x) – check if string ends with the string specified by x<\/li>\n
- find(x) – checks if string contains string specified by x and returns the index if found else returns -1<\/li>\n
- replace(x, y) – replaces all occurrences of string x with string y<\/li>\n
- split(x) – splits a string into a list using the delimiter specified by string x<\/li>\n
- join(x) – reverse of split() . Converts separate strings in a list into a string using this string as a delimiter<\/li>\n<\/ul>\n
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The startswith() and endswith() methods are case-sensitive as are the other methods. The split() and join() methods deal with lists which we will read about in the next posts.<\/p>\n
There are other string methods, but the ones mentioned above are the basic methods which cover all the possible operations on strings.<\/p>\n
In the next post we look at lists<\/a> .<\/p>\n","protected":false},"excerpt":{"rendered":"