# Comparison Operators in Python

Python Methods and Functions

Checking more than two conditions is very common in programming languages. Let's say we want to check the below condition:

`  a & lt; b & lt; c  `

The most common syntax for this is:

`  if a & lt; b and b & lt; c: {...}  `

There is a better way to write this in Python using the Chaining comparison operator . A statement chain can be written like this:

`  if a & lt; b & lt; c: {.....}  `

According to

Chaining comparison operators:

1. Comparisons yield Boolean values: True or False.
2. Comparisons can be linked arbitrarily. For example:
`  x & lt; y & lt; = z is equivalent to x & lt; y and y & lt; = z, `

except that y is evaluated only once.
(but in both cases z is not evaluated at all when x & lt; y turns out to be false).

3. Formally, if a, b, c,…, y, z — expressions and op1, op2, ..., opN — comparison operators, then a op1 b op2 c… y opN z is equivalent to op1 b and b op2 c and… y opN z, except that each expression is evaluated at most once.
4. Also,
`  a op1 b op2 c `

does not imply any comparison between a and c, therefore

`  ac  `

perfectly legal.

 ` # Python code for illustration ` ` # string comparison operators ` ` x ` ` = ` ` 5 ` ` print ` ` (` ` 1 ` ` & lt; x & lt; ` ` 10 ` `) ` ` print ` ` (` ` 10 ` ` & lt; x & lt; ` ` 20 ` `) ` ` print ` ` (x & lt; ` ` 10 ` ` & lt; x ` ` * ` ` 10 ` ` & lt; ` ` 100 ` `) ` ` print ` ` (` ` 10 ` ` & gt; x & lt; ` ` = ` ` 9 ` `) ` ` print ` ` (` ` 5 ` ` = ` ` = ` ` x & gt; ` ` 4 ` `) `

Output:

` True False True True `

Another example:

` # Python code for illustration `
` # string comparison operators `

` a, b, c, d, e, f ` ` = ` ` 0 ` `, ` ` 5 ` `, ` ` 12 ` `, ` ` 0 ` `, ` ` 15 ` `, ` ` 15 `

` exp1 ` ` = ` ` a & lt ; ` ` = ` ` b & lt; c & gt; d ` ` is ` ` not ` ` e ` ` is ` ` f `

` exp2 ` ` = ` ` a ` ` is ` ` d & gt; f ` ` is ` ` not ` ` c `

` print ` ` (exp1) `

` print ` ` (exp2) `

Output:

` True False `

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