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Appropriate datatype for holding percent values?
...to 1.00. For instance:
declare @discount numeric(9,9)
, @quantity int
select @discount = 0.999999999
, @quantity = 10000
select convert(money, @discount * @quantity)
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Convert data.frame column format from character to factor
...yr::mutate_if() to convert all character columns or dplyr::mutate_at() for select named character columns to factors:
library(dplyr)
# all character columns to factor:
df <- mutate_if(df, is.character, as.factor)
# select character columns 'char1', 'char2', etc. to factor:
df <- mutate_at(d...
How do you test private methods with NUnit?
...
This should be the selected answer, as it is the only one which actually answers the question.
– bavaza
Dec 10 '13 at 16:04
...
Unable to type in Visual Studio
...hange the "Source Control Plug-In" to "None" (Source Control -> Plug-in Selection)
Restart Visual Studio
Repeat steps 1-3, except re-enable AnkhSVN in step 2
I was able to edit files again after this.
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How to calculate time in hours between two dates in iOS
...developer.apple.com/library/mac/navigation/
or if you are using Xcode just select help/documentation from the menu.
See: how-to-convert-an-nstimeinterval-seconds-into-minutes
--edit: See ÐąrέÐέvil's answer below for correctly handling daylight savings/leap seconds
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Postgres: “ERROR: cached plan must not change result type”
...ng this error.
My application opened a database connection and prepared a SELECT statement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the applic...
LINQ .Any VS .Exists - What's the difference?
... Enumerable.Repeat("ABCDEFGHIJKLMNOPQRSTUVWXYZ", 13)
.Select(s =>
{
var cryptoResult = new byte[4];
new RNGCryptoServiceProvider().GetBytes(cryptoResult);
return s[new Random(BitConverter.ToInt32(cryp...
Enabling auto layout in iOS 6 while remaining backwards compatible with iOS 5
...tolayout can be enabled or disabled on each .storyboard or .xib file. Just select the particular file and modify the "Use Autolayout" property using the File inspector in Xcode:
Using autolayout enabled interface files with the deployment target set to an iOS version prior to 6.0 results in compi...
PDO support for multiple queries (PDO_MYSQL, PDO_MYSQLND)
...
Then
try {
$db->query('SET NAMES gbk');
$stmt = $db->prepare('SELECT * FROM 2_1_paidused WHERE NumberRenamed = ? LIMIT 1');
$stmt->execute(array("\xbf\x27 OR 1=1 /*"));
}
catch (PDOException $e){
echo "DataBase Errorz: " .$e->getMessage() .'<br>';
}
catch (Exception $e...
How can I filter lines on load in Pandas read_csv function?
... read_csv. However, read_csv returns a DataFrame, which can be filtered by selecting rows by boolean vector df[bool_vec]:
filtered = df[(df['timestamp'] > targettime)]
This is selecting all rows in df (assuming df is any DataFrame, such as the result of a read_csv call, that at least contains ...