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How do Trigonometric functions work?
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Note that the table of values used by CORDIC must be pre-calculated. So, Taylor might still be used at "compile time".
– Rhubbarb
May 22 '13 at 21:38
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Transpose a data frame
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You can use the transpose function from the data.table library. Simple and fast solution that keeps numeric values as numeric.
library(data.table)
# get data
data("mtcars")
# transpose
t_mtcars <- transpose(mtcars)
# get row and colnames in order
colnames(t_mtc...
MySQL query String contains
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Quite simple actually:
mysql_query("
SELECT *
FROM `table`
WHERE `column` LIKE '%{$needle}%'
");
The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grows you'll need to use fulltext indice...
SQL Server: Examples of PIVOTing String data
...on will work on text as well as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
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When to use Hadoop, HBase, Hive and Pig?
.... It's a distributed, scalable, big data store, modelled after Google's BigTable. It stores data as key/value pairs.
Coming to Hive. It provides us data warehousing facilities on top of an existing Hadoop cluster. Along with that it provides an SQL like interface which makes your work easier, in ca...
How do I view the SQLite database on an Android device? [duplicate]
...le Java activity file; just add it to your source folder.
You can view the tables in your app database, update, delete, insert rows to you table. Everything from inside your app.
When the development is done remove the Java file from your src folder. That's it.
You can view the 5 minute demo, Data...
What is the recommended batch size for SqlBulkCopy?
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One thing to consider is if the table is empty and has indexes. In those cases you might want to upload everything in one batch as mentioned here: technet.microsoft.com/en-us/library/ms177445(v=sql.105).aspx "If you bulk import data into an empty table with...
How to use an existing database with an Android application [duplicate]
...r getTestData() {
try {
String sql ="SELECT * FROM myTable";
Cursor mCur = mDb.rawQuery(sql, null);
if (mCur != null) {
mCur.moveToNext();
}
return mCur;
} catch (SQLException mSQLException) {
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TSQL - How to use GO inside of a BEGIN .. END block?
...t using SET NOEXEC.
IF not whatever
BEGIN
SET NOEXEC ON;
END
ALTER TABLE dbo.EMPLOYEE ADD COLUMN EMP_IS_ADMIN BIT NOT NULL
GO
UPDATE dbo.EMPLOYEE SET EMP_IS_ADMIN = whatever
SET NOEXEC OFF;
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Laravel Schema onDelete set null
Can't figure out how to set proper onDelete constraint on a table in Laravel. (I'm working with SqLite)
4 Answers
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