How to use boolean and in Python

Question

In C  we can use  amp  amp   boolean and  like this   int i   5  int ii   10  if i    5  amp  amp  ii    10        Console WriteLine  i is 5  and ii is 10      Console ReadKey true     But try that with python   i   5 ii   10 if i    5  amp  amp  ii    10      print  i is 5 and ii is 10           I get an error  SyntaxError  invalid syntax  If I use a single  amp   at least I get no syntax error   How do I do a boolean  amp  amp  in Python

User · Answer

In python  use and instead of  amp  amp  like this      usr bin python foo   True  bar   True  if foo and bar      print  both are true     This prints   both are true

User · Answer

amp  is used for bit-wise comparison  use and instead  and btw  you don t need semicolon at the end of print statement

User · Answer

Try this   i   5 ii   10 if i    5 and ii    10        print  i is 5 and ii is 10    Edit  Oh  and you dont need that semicolon on the last line  edit to remove it from my code

User · Answer

You can also test them as a couple   if  i ii    5 10       print  i is 5 and ii is 10

User · Answer

As pointed out    amp   in python performs a bitwise and operation  just as it does in C   and is the appropriate equivalent to the  amp  amp  operator   Since we re dealing with booleans  i    5 is True and ii    10 is also True   you may wonder why this didn t either work anyway  True being treated as an integer quantity should still mean True  amp  True is a True value   or throw an exception  eg  by forbidding bitwise operations on boolean types   The reason is operator precedence   The  and  operator binds more loosely than     so the expression      i  5 and ii  10  is equivalent to    i  5  and  ii  10    However  bitwise  amp  has a higher precedence than       since you wouldn t want expressions like  a  amp  0xff    ch  to mean  a  amp   0xff    ch     so the expression would actually be interpreted as   if i     5  amp  ii     10    Which is using python s operator chaining to mean  does the valuee of ii anded with 5 equal both i and 10   Obviously this will never be true   You would actually get  seemingly  the right answer if you had included brackets to force the precedence  so   if  i  5   amp   ii 10    would cause the statement to be printed   It s the wrong thing to do  however -   amp   has many different semantics to  and  -  precedence  short-cirtuiting  behaviour with integer arguments etc   so it s fortunate that you caught this here rather than being fooled till it produced less obvious bugs

User · Answer

The correct operator to be used are the keywords  or  and  and   which in your example  the correct way to express this would be   if i    5 and ii    10      print  i is 5 and ii is 10    You can refer the details in the  Boolean Operations  section in the language reference

[python] How to use boolean 'and' in Python

Examples related to python

Examples related to boolean-logic