String Indexing and String Slicing in Python

String Indexing and String Slicing in Python:

(1) Strings are identified as a contiguous set of characters represented in quotation marks. Python allows single quotes, double quotes, and triple quotes. Python treats single quotes and double quotes in the same manner. When we use triple quotes, strings can span several lines without using the escape character.

(2) Each individual character in a string can be accessed using a technique called indexing. Python indexes the characters in a string from left to right and from right end to left. From left to right, the first character of a string has the index 0 and from the right end to left, the first character of the string is -1 as shown below.

(3) Example of String Indexing:

• From Left to Right:

• From Right to Left:

(4) In addition to extracting individual characters in a string, you can pick out a group of characters by slicing strings. Slicing works a lot like indexing, but you use two offsets separated by a colon (:) character. The first offset is where Python should start slicing from; the second offset is where it should stop slicing. Again, think of the offsets as the spaces between the characters, not as the characters themselves.

(5) Example of String Slicing:

• From Left to Right:

The first line print(x[0:4]) tells Python to slice between offset 0 and 4. You can see from the above table that there are four characters between these offsets, that’s why we get the output GK S. Similarly for the second line print(y[0:4]). The third line print(x[4:7]) tells Python to slice between offsets 4 and 7. You can see from the above table that there are three characters between these offsets, that’s why we get the output CIE. Similarly for the fourth line print(y[4:7]). The fifth line print(x[0::2]) slices from the beginning to the end of the string, but since the step value is 2, it takes every second character. Similarly for the sixth line print(y[0::2])

• From Right to Left: