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print(2==2==True)

gives the result : False

so my query is why it doesn't give answer as True?

Where as :

print(2==2 and True)

gives the result: True

can anyone give a satisfactory answer?

Ch3steR
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Srikrishnan Adhiseshan
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  • Does this answer your question? [Why is `True is False == False`, False in Python? \[duplicate\]](https://stackoverflow.com/questions/31354429/why-is-true-is-false-false-false-in-python) – MisterMiyagi Jun 27 '22 at 06:50

4 Answers4

3

When you do:

print(a == b == c)

You are checking if the values of a, b, and c are the same. Since 2 is NOT equal to True, the statement is false, and the output of

print(2 == 2 == True)

will be False.

However, when you do:

print(2 == 2 and True)

You are checking that if BOTH 2 == 2 and True have the boolean values of True, then you will print out True, and otherwise False. Since 2 does equal 2, the expression 2 == 2 is True. Thus, True and True is True, so the output will be True.

Let me know if you have sny further questions or clarifications!

Aniketh Malyala
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  • To add to this, you can run `print((2 == 2) == True)` to check if 2 == 2 was True as it will first check whether 2 is 2, before comparing the result (True / False) with the True statement at the end. Although i'm not seeing why this would be necessary. – sktan Jun 27 '22 at 05:33
  • so in the first scenario 2==2 basically will imply 2==True if my query is right? – Srikrishnan Adhiseshan Jun 27 '22 at 05:34
  • 2 == 2 is the same as True, but 2 == 2 == True is asking "are 2, 2, and True all the same values?" – Aniketh Malyala Jun 27 '22 at 06:09
1

From python docs:

Comparisons:

Comparisons can be chained arbitrarily, e.g., x < y <= z is equivalent to x < y and y <= z, except that y is evaluated only once (but in both cases z is not evaluated at all when x < y is found to be false).

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

In your first example,

print(2 == 2 == True) # This is in the form `a op b op c`

is equivalent to 2 == 2 and 2 == True. which is True and False.

In your second example, there would be no chaining since and is not comparison operator.

print(2 == 2 and True)

is equivalent to 2 == 2 and True, which is True and True.

If you want to force evaluation of an expression first then put the expression inside ().

print((2 == 2) == True)
print((2 == 2) and True)
Ch3steR
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0

In the first Case 2==2==True You are testing three conditions which is like.

  1. 2==2 => True
  2. 2==True => False
  3. True==2 => False (Don't need check because if first 2 fulfills then this one is also true

and in Second Case `2==2 and True' You are testing two conditions which is like.

  1. 2==2 => True
  2. True and True => True
Hiren Namera
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The == operator compares the value or equality of objects. print(2==2==True) means you are comparing three objects together. 2 equals 2 as both values are equal but 2 and 2 is value whereas True is equality so overall value becomes false.

print(2==2 and True) means you are comparing equality of 2==2 and True. 2 equals 2 as both values are equal and equality is True. True is equality so True and True equality becomes true.

Pujan Bade
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