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How do I replace NA values with zeros in an R dataframe?
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See my comment in @gsk3 answer. A simple example:
> m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10...
How do I improve ASP.NET MVC application performance?
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A compiled list of possible sources of improvement are below:
General
Make use of a profiler to discover memory leaks and performance problems in your application. personally I suggest dotTrace
Run your site in Release mode,...
How to calculate the time interval between two time strings
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158
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How can I remove a character from a string using Javascript?
...ince everyone's having so much fun here and user1293504 doesn't seem to be coming back any time soon to answer clarifying questions, here's a method to remove the Nth character from a string:
String.prototype.removeCharAt = function (i) {
var tmp = this.split(''); // convert to an array
tmp...
How to create a SQL Server function to “join” multiple rows from a subquery into a single delimited
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If you're using SQL Server 2005, you could use the FOR XML PATH command.
SELECT [VehicleID]
, [Name]
, (STUFF((SELECT CAST(', ' + [City] AS VARCHAR(MAX))
FROM [Location]
WHERE (VehicleID = Vehicle.VehicleID)
FOR XML PATH ('')), 1, 2, '')) AS Locati...
How to force keyboard with numbers in mobile website in Android
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51
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How to print HTML content on click of a button, but not the page? [duplicate]
... edited May 23 '17 at 12:10
Community♦
111 silver badge
answered Jun 3 '13 at 11:05
asprinasprin
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registerForRemoteNotificationTypes: is not supported in iOS 8.0 and later
...ut any iOS 8 selectors) and Xcode 6, then you will need to use conditional compiling as follows:
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 80000
if ([application respondsToSelector:@selector(registerUserNotificationSettings:)]) {
// use registerUserNotificationSettings
} else {
// use regis...
CSS3 selector :first-of-type with class name?
... edited May 23 '17 at 12:18
Community♦
111 silver badge
answered Jun 22 '11 at 22:00
BoltClock♦BoltClo...
Location of my.cnf file on macOS
...lean install of MySQL 5.7.19 on Mac OS 10.12 using the .dmg from dev.mysql.com. There's no my.cnf in any of the places that mysql --help says it looks in. And there's no my-default.cnf in /usr/local/mysql/support-files/ or anywhere else I've found. Turns out that "as of MySQL 5.7.18, my-default.cnf ...