comparison interview questions
Top comparison frequently asked interview questions
After searching through some existing libraries for JSON, I have finally ended up with these two:
I am a bit partial towards GSON, but word on the net is that GSon suffers from a certain celestial performance issue (as of Sept 2009).
I am continuing my comparison; in the meantime, I'm looking for help to make up my mind.
Source: (StackOverflow)
I have two objects in C# and don't know if it's Boolean or any other type.
However when I try to compare those C# fails to give the right answer.
I have tried the same code with VB.NET and that did it !
Can anyone tell me how to fix this if there is a solution ?
C#:
object a = true;
object b = true;
object c = false;
if (a == b) c = true;
MessageBox.Show(c.ToString()); //Outputs False !!
VB.NET:
Dim a As Object = True
Dim b As Object = True
Dim c As Object = False
If (a = b) Then c = True
MessageBox.Show(c.ToString()) '// Outputs True
Source: (StackOverflow)
What's the best way to do case insensitive string comparison in Python?
I would like to encapsulate comparison of a regular strings to a repository string using in a very simple and pythonic way. I also would like to have ability to look up values in a dict hashed by strings using regular python strings. Much obliged for advice.
Source: (StackOverflow)
I'm trying to get started with unit testing in Python and I was wondering if someone could inform me of the advantages and disadvantages of doctest and unittest. What conditions would you use each for?
Source: (StackOverflow)
I am trying to figure out a way of checking for the existence of a value in an array without iterating through the array.
I am reading a file for a parameter. I have a long list of parameters I do not want to deal with. I placed these unwanted parameters in an array @badparams
.
I want to read a new parameter and if it does not exist in @badparams
, process it. If it does exist in @badparams
, go to the next read.
Source: (StackOverflow)
I'm trying to make a function that will compare multiple variables to an integer and output a string of three letters. I was wondering if there was a way to translate this into Python. So say:
x = 0
y = 1
z = 3
Mylist = []
if x or y or z == 0 :
Mylist.append("c")
elif x or y or z == 1 :
Mylist.append("d")
elif x or y or z == 2 :
Mylist.append("e")
elif x or y or z == 3 :
Mylist.append("f")
which would return a list of
["c", "d", "f"]
Is something like this possible?
Source: (StackOverflow)
I've got a Python program where two variables are set to the value 'public'
. In a conditional expression I have the comparison var1 is var2
which fails, but if I change it to var1 == var2
it returns True
.
Now if I open my Python interpreter and do the same "is" comparison, it succeeds.
>>> s1 = 'public'
>>> s2 = 'public'
>>> s2 is s1
True
What am I missing here?
Source: (StackOverflow)
I'm looking to create a base table of images and then compare any new images against that to determine if the new image is an exact (or close) duplicate of the base.
For example: if you want to reduce storage of the same image 100's of times, you could store one copy of it and provide reference links to it. When a new image is entered you want to compare to an existing image to make sure it's not a duplicate ... ideas?
One idea of mine was to reduce to a small thumbnail and then randomly pick 100 pixel locations and compare.
Source: (StackOverflow)
Possible Duplicate:
How do you determine equality for two JavaScript objects?
What is the best way to compare objects in JavaScript?
Example:
var user1 = {name : "nerd", org: "dev"};
var user2 = {name : "nerd", org: "dev"};
var eq = user1 == user2;
alert(eq); // gives false
I know that two objects are equal if they refer to the exact same object, but is there a way to check if they have the same attributes' values?
The following way works for me, but is it the only possibility?
var eq = Object.toJSON(user1) == Object.toJSON(user2);
alert(eq); // gives true
Source: (StackOverflow)
I am trying to understand the difference between these four methods. I know by default that ==
calls the method equal?
which returns true when both operands refer to exactly the same object.
===
by default also calls ==
which calls equal?
... okay, so if all these three methods are not overridden, then I guess
===
, ==
and equal?
do exactly the same thing?
Now comes eql?
. What does this do (by default)? Does it make a call to the operand's hash/id?
Why does Ruby have so many equality signs? Are they supposed to differ in semantics?
Source: (StackOverflow)
This question already has an answer here:
I noticed a Python script I was writing was acting squirrelly, and traced it to an infinite loop, where the loop condition was while line is not ''
. Running through it in the debugger, it turned out that line was in fact ''
. When I changed it to !=''
rather than is not ''
, it worked fine.
Also, is it generally considered better to just use '==' by default, even when comparing int or Boolean values? I've always liked to use 'is' because I find it more aesthetically pleasing and pythonic (which is how I fell into this trap...), but I wonder if it's intended to just be reserved for when you care about finding two objects with the same id.
Source: (StackOverflow)
Why does the following behave unexpectedly in Python?
>>> a = 256
>>> b = 256
>>> a is b
True # This is an expected result
>>> a = 257
>>> b = 257
>>> a is b
False # What happened here? Why is this False?
>>> 257 is 257
True # Yet the literal numbers compare properly
I am using Python 2.5.2. Trying some different versions of Python, it appears that Python 2.3.3 shows the above behaviour between 99 and 100.
Based on the above, I can hypothesize that Python is internally implemented such that "small" integers are stored in a different way than larger integers and the is
operator can tell the difference. Why the leaky abstraction? What is a better way of comparing two arbitrary objects to see whether they are the same when I don't know in advance whether they are numbers or not?
Source: (StackOverflow)
This question already has an answer here:
I am trying to optimize a function which does binary search of strings in Javascript.
Binary search requires you to know whether the key is ==
the pivot or <
the pivot.
But this requires two string comparisons in Javascript, unlike in C
like languages which have the strcmp()
function that returns three values (-1, 0, +1) for (less than, equal, greater than).
Is there such a native function in Javascript, that can return a ternary value so that just one comparison is required in each iteration of the binary search?
Source: (StackOverflow)
It seems that there is no real pattern to the way functions are named, str_replace, strrpos, strip_tags, stripslashes are just some.
Why is this the case?
EDIT - this wasn't meant as a "troll" type post - just something that I think everytime I use the language!
Source: (StackOverflow)