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SQL Server - stop or break execution of a SQL script
...hi
Msg 2745, Level 16, State 2, Line 1
Process ID 51 has raised user error 50000, severity 20. SQL Server is terminating this process.
Msg 50000, Level 20, State 1, Line 1
Oh no a fatal error
Msg 0, Level 20, State 0, Line 0
A severe error occurred on the current command. The results, if any, shoul...
What's the fastest way to merge/join data.frames in R?
...w data.table and dplyr :)
Larger data set:
N <- 1e8
g1 <- sample(1:50000, N, replace = TRUE)
g2<- sample(1:50000, N, replace = TRUE)
d <- data.frame(x=sample(N,N), y=rnorm(N), g1, g2)
Took around 10-13GB of ram just to hold the data before running the benchmark.
Results:
...
Count number of occurences for each unique value
...
This works for me. Take your vector v
length(summary(as.factor(v),maxsum=50000))
Comment: set maxsum to be large enough to capture the number of unique values
or with the magrittr package
v %>% as.factor %>% summary(maxsum=50000) %>% length
...
How to get last N records with activerecord?
...t(5)
because:
Something.last(5).class
=> Array
so:
Something.last(50000).count
will likely blow up your memory or take forever.
Good approach:
Something.limit(5).order('id desc')
because:
Something.limit(5).order('id desc').class
=> Image::ActiveRecord_Relation
Something.limit(5)...
Very large matrices using Python and NumPy
...begins to struggle with anything much larger (trying to create a matrix of 50000 x 50000 fails). Obviously, this is because of the massive memory requirements.
...
Convert timestamp in milliseconds to string formatted time in Java
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Division is not associative: 50000 / (1000 * 60) = 0.8333333333 while 50000 / 1000 * 60= 3000.
– farnett
Feb 16 '15 at 22:05
3
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Counting the number of True Booleans in a Python List
... my results:
>>> a = [bool(random.getrandbits(1)) for x in range(50000)]
>>> len(a)
50000
>>> a.count(False)
24884
>>> a.count(True)
25116
>>> def count_it(a):
... curr = time.time()
... counting = a.count(True)
... print("Count it = " + str(time.t...
Adding two Java 8 streams, or an extra element to a stream
...
If you add static imports for Stream.concat and Stream.of, the first example could be written as follows:
Stream<Foo> stream = concat(stream1, concat(stream2, of(element)));
Importing static methods with generic names can result in code that becomes dif...
How to remove multiple indexes from a list at the same time? [duplicate]
...e for the different ways so I performed a test on removing 5000 items from 50000 in all 3 generally different approaches, and for me numpy was the winner (if you have elements that fit in numpy):
7.5 sec for the enumerated list comprehension [4.5 sec on another PC]
0.08 sec for deleting items in r...
Elegant way to combine multiple collections of elements?
...
I think you might be looking for LINQ's .Concat()?
var combined = foo.Concat(bar).Concat(foobar).Concat(...);
Alternatively, .Union() will remove duplicate elements.
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