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Are there pronounceable names for common Haskell operators? [closed]
...lt;|> or / alternative expr <|> term: "expr or term"
++ concat / plus / append
[] empty list
: cons
:: of type / as f x :: Int: f x of type Int
\ lambda
@ as go ll@(l:ls): go ll as l cons ls
~ lazy go ~(a,b): go la...
How do I combine two data frames?
...
You can also use pd.concat, which is particularly helpful when you are joining more than two dataframes:
bigdata = pd.concat([data1, data2], ignore_index=True, sort=False)
...
Remove all spaces from a string in SQL Server
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Simply replace it;
SELECT REPLACE(fld_or_variable, ' ', '')
Edit:
Just to clarify; its a global replace, there is no need to trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))...
Is SQL or even TSQL Turing Complete?
...(0);
-- Initialization of temporary variables
DECLARE @CodeLength INT = (SELECT COUNT(*) FROM @CodeTable);
DECLARE @CodeIndex INT = 0;
DECLARE @Pointer INT = 1;
DECLARE @InputIndex INT = 0;
DECLARE @Command CHAR(1);
DECLARE @Depth INT;
-- Main calculation cycle
WHILE @CodeIndex < @...
Joining three tables using MySQL
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Simply use:
select s.name "Student", c.name "Course"
from student s, bridge b, course c
where b.sid = s.sid and b.cid = c.cid
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How to get the difference between two arrays of objects in JavaScript
...er(comparer(b));
var onlyInB = b.filter(comparer(a));
result = onlyInA.concat(onlyInB);
console.log(result);
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How can I determine if a date is between two dates in Java? [duplicate]
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Is this better than the "selected solved answer"?
– Christian Moen
Jan 21 '17 at 23:01
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s...
What's the difference between VARCHAR and CHAR?
...CHAR(10),
Street VARCHAR(10));
Insert into temp
values('Pune','Oxford');
select length(city), length(street) from temp;
Output will be
length(City) Length(street)
10 6
Conclusion: To use storage space efficiently must use VARCHAR Instead CHAR if variable length is ...
Most efficient way to prepend a value to an array
...g an array to the front of another array, it is more efficient to just use concat. So:
var newArray = values.concat(oldArray);
But this will still be O(N) in the size of oldArray. Still, it is more efficient than manually iterating over oldArray. Also, depending on the details, it may help you, b...
Creating dataframe from a dictionary where entries have different lengths
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You can also use pd.concat along axis=1 with a list of pd.Series objects:
import pandas as pd, numpy as np
d = {'A': np.array([1,2]), 'B': np.array([1,2,3,4])}
res = pd.concat([pd.Series(v, name=k) for k, v in d.items()], axis=1)
print(res)
...