logical-operators

I would like the element-wise logical OR operator. I know "or" itself is not what I am looking for. I am aware that AND corresponds to & and NOT, ~ . But what about OR? deinonychusaur The corresponding operator is | : df[(df < 3) | (df == 5)] would elementwise check if value is less than 3 or equal to 5. If you need a function to do this, we have np.logical_or . For two conditions, you can use df[np.logical_or(df<3, df==5)] Or, for multiple conditions use the logical_or.reduce , df[np.logical_or.reduce([df<3, df==5])] Since the conditions are specified as individual arguments, parentheses

Introduction to problem setup I was doing some benchmarks involving - ~A and A==0 for a double array with no NaNs , both of which convert A to a logical array where all zeros are converted to true values and rest are set as false values. For the benchmarking, I have used three sets of input data – Very small to small sized data - 15:5:100 Small to medium sized data - 50:40:1000 Medium to large sized data - 200:400:3800 The input is created with A = round(rand(N)*20) , where N is the parameter taken from the size array. Thus, N would vary from 15 to 100 with stepsize of 5 for the first set and

Possible Duplicate: What is the diffference between the | and || or operators? Logical AND and OR: (x & y) (x | y) Conditional AND and OR: (x && y) (x || y) I've only known about conditional operands up to this point. I know what it does and how to apply it in if-statements. But what is the purpose of logical operands? I prefer to think of it as "bitwise vs. conditional" rather than "logical vs conditional" since the general concept of "logical" applies in both cases. x & y // bitwise AND, 0101 & 0011 = 0001 x | y // bitwise OR, 0101 | 0011 = 0111 x && y // true if both x and y are true x || y

The short circuiting behaviour of the operators && and || is an amazing tool for programmers. But why do they lose this behaviour when overloaded? I understand that operators are merely syntactic sugar for functions but the operators for bool have this behaviour, why should it be restricted to this single type? Is there any technical reasoning behind this? Eric Lippert All design processes result in compromises between mutually incompatible goals. Unfortunately, the design process for the overloaded && operator in C++ produced a confusing end result: that the very feature you want from && --

Why is there no logical xor in JavaScript? JavaScript traces its ancestry back to C, and C does not have a logical XOR operator. Mainly because it's not useful. Bitwise XOR is extremely useful, but in all my years of programming I have never needed a logical XOR. If you have two boolean variables you can mimic XOR with: if (a != b) With two arbitrary variables you could use ! to coerce them to boolean values and then use the same trick: if (!a != !b) That's pretty obscure though and would certainly deserve a comment. Indeed, you could even use the bitwise XOR operator at this point, though