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Quickly reading very large tables as dataframes
...umeric","integer")))
## user system elapsed
## 10.20 0.03 10.32
fread
require(data.table)
system.time(DT <- fread("test.csv"))
## user system elapsed
## 3.12 0.01 3.22
sqldf
require(sqldf)
system.time(SQLDF <- read.csv.sql("test...
Disable all table constraints in Oracle
...m SQL*Plus or put this thing into a package or procedure. The join to USER_TABLES is there to avoid view constraints.
It's unlikely that you really want to disable all constraints (including NOT NULL, primary keys, etc). You should think about putting constraint_type in the WHERE clause.
BEGIN
...
Is there a read-only generic dictionary available in .NET?
...lt;TKey, TValue>
{
private readonly IDictionary<TKey, TValue> _dictionary;
public ReadOnlyDictionary()
{
_dictionary = new Dictionary<TKey, TValue>();
}
public ReadOnlyDictionary(IDictionary<TKey, TValue> dictionary)
{
_dictionary = dict...
How do you get the index of the current iteration of a foreach loop?
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Neuron
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answered Sep 4 '08 at 1:46
FlySwatFlySwat
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How can I expand the full path of the current file to pass to a command in Vim?
... Umber FerruleUmber Ferrule
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5
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How to reload a clojure file in REPL
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Martin Puppe
3266 bronze badges
answered Sep 22 '14 at 17:16
Dirk GeursDirk Geurs
2,1571717...
Can't pickle when using multiprocessing Pool.map()
...r program to allow such methods to be pickled, registering it with the copy_reg standard library method.
For example, Steven Bethard's contribution to this thread (towards the end of the thread) shows one perfectly workable approach to allow method pickling/unpickling via copy_reg.
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How to reshape data from long to wide format
...
@indra_patil - I would likely use the reshape2 package as indicated in one of the other answers. You could create a new question that's specific to your use case and post it if you can't figure it out.
– Chase...
Best approach for designing F# libraries for use from both F# and C#
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
What is “thread local storage” in Python, and why do I need it?
...
Shog9
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answered Sep 20 '08 at 0:31
Aaron MaenpaaAar...