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How to join two sets in one line without using “|”
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320
You can use union method for sets: set.union(other_set)
Note that it returns a new set i.e it...
Convert a row of a data frame to vector
... Chinmay PatilChinmay Patil
15.7k44 gold badges3232 silver badges5555 bronze badges
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Run an OLS regression with Pandas Data Frame
...df = pd.DataFrame({"A": [10,20,30,40,50], "B": [20, 30, 10, 40, 50], "C": [32, 234, 23, 23, 42523]})
>>> result = sm.ols(formula="A ~ B + C", data=df).fit()
>>> print(result.params)
Intercept 14.952480
B 0.401182
C 0.000352
dtype: float64
>>> pri...
Why is it slower to iterate over a small string than a small list?
...> >> 31 POP_TOP
#>>> 32 LOAD_CONST 0 (None)
#>>> 35 RETURN_VALUE
def string_iterate():
[item for item in "abc"]
dis.dis(string_iterate)
#>>> 2 0 BUILD_LIST 0
#&g...
What are the advantages of NumPy over regular Python lists?
...ou definitely would for a billion cells -- neither approach would fit in a 32-bit architecture, but with 64-bit builds NumPy would get away with 4 GB or so, Python alone would need at least about 12 GB (lots of pointers which double in size) -- a much costlier piece of hardware!
The difference is m...
What is the most efficient/elegant way to parse a flat table into a tree?
...te a structure
CREATE TABLE tree (
id int NOT NULL,
name varchar(32) NOT NULL,
parent_id int NULL,
node_order int NOT NULL,
CONSTRAINT tree_pk PRIMARY KEY (id),
CONSTRAINT tree_tree_fk FOREIGN KEY (parent_id)
REFERENCES tree (id) NOT DEFERRABLE
);
insert into tr...
How to make inline functions in C#
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IL_0027: callvirt instance !1 class [mscorlib]System.Func`2<int32, int32>::Invoke(!0)
IL_002c: box [mscorlib]System.Int32
IL_0031: call string [mscorlib]System.String::Format(string, object)
IL_0036: call void [mscorlib]System.Console::WriteLine(string)
...
What are the mechanics of short string optimization in libc++?
...tore a short string (i.e. largest capacity() without an allocation).
On a 32 bit machine, 10 chars will fit in the short string. sizeof(string) is 12.
On a 64 bit machine, 22 chars will fit in the short string. sizeof(string) is 24.
A major design goal was to minimize sizeof(string), while maki...
Getting a list of all subdirectories in the current directory
...se
– James McMahon
Aug 22 '12 at 20:32
5
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Can I list-initialize a vector of move-only type?
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XeoXeo
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