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Comparing strings with == which are declared final in Java
...l runtime, thus leading to the creation of a new String object. You can verify this by comparing byte code of both the codes.
The first code example (non-final version) is compiled to the following byte code:
Code:
0: ldc #2; //String str
2: astore_1
3: ldc #3; //String in...
Finding the mode of a list
...(a), key=a.count)) returns 11. Will it always return the minimum mode? And if so, why?
– battey
Jan 13 '19 at 22:54
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show 4 more comments
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Default value of 'boolean' and 'Boolean' in Java
...ery wrapper uses a reference which has a default of null. Primitives have different default values:
boolean -> false
byte, char, short, int, long -> 0
float, double -> 0.0
Note (2): void has a wrapper Void which also has a default of null and is it's only possible value (without using ...
difference between #if defined(WIN32) and #ifdef(WIN32)
...
If you use #ifdef syntax, remove the brackets.
The difference between the two is that #ifdef can only use a single condition,
while #if defined(NAME) can do compound conditionals.
For example in your case:
#if defined(WIN...
Does Go have “if x in” construct similar to Python?
Without iterating over the entire array, how can I check if x in array using Go? Does the language have a construct?
7 A...
Float vs Decimal in ActiveRecord
...ever to use floats for currency.
The reason for that is how the IEEE specification defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to st...
How to pass all arguments passed to my bash script to a function of mine? [duplicate]
... That is "$@" is equivalent to "$1" "$2" "$3"....
Passing some arguments:
If you want to pass all but the first arguments, you can first use shift to "consume" the first argument and then pass "$@" to pass the remaining arguments to another command. In bash (and zsh and ksh, but not in plain POSIX...
How to determine equality for two JavaScript objects?
A strict equality operator will tell you if two object types are equal. However, is there a way to tell if two objects are equal, much like the hash code value in Java?
...
count the frequency that a value occurs in a dataframe column
...38]:
df['a'].value_counts()
Out[38]:
b 3
a 2
s 2
dtype: int64
If you wanted to add frequency back to the original dataframe use transform to return an aligned index:
In [41]:
df['freq'] = df.groupby('a')['a'].transform('count')
df
Out[41]:
a freq
0 a 2
1 b 3
2 s 2
3 s...
Numpy first occurrence of value greater than existing value
...
Just a word of caution: if there's no True value in its input array, np.argmax will happily return 0 (which is not what you want in this case).
– ambrus
Feb 7 '14 at 13:15
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