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Scheduling R Script
..., to run scheduler first install below packages
install.packages('data.table')
install.packages('knitr')
install.packages('miniUI')
install.packages('shiny')
install.packages("taskscheduleR", repos = "http://www.datatailor.be/rcube", type =
"source")
After installing go to
**TOOLS...
Is there an opposite to display:none?
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When changing element's display in Javascript, in many cases a suitable option to 'undo' the result of element.style.display = "none" is element.style.display = "". This removes the display declaration from the style attribute, reverting the actual value of display property to the value set...
How to Use Order By for Multiple Columns in Laravel 4?
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Is there a way to add an orderBy on an established query?
– Rafael
Jan 16 '15 at 21:43
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SHA512 vs. Blowfish and Bcrypt [closed]
...nd others. It's good, but flaws have been recognized that, while not exploitable now, have led to the the SHA-3 competition for new hash algorithms. Also, keep in mind that the study of hash algorithms is "newer" than that of ciphers, and cryptographers are still learning about them.
Even though bc...
PowerShell script to return versions of .NET Framework on a machine?
...me, Version, Release
Based on the MSDN article, you could build a lookup table and return the marketing product version number for releases after 4.5:
$Lookup = @{
378389 = [version]'4.5'
378675 = [version]'4.5.1'
378758 = [version]'4.5.1'
379893 = [version]'4.5.2'
393295 = [v...
Switch on Enum in Java [duplicate]
...r speed, the switch statement approach might be faster because it's just a table lookup in the bytecode. With your approach, you have to push a new function onto the stack. It's a micro-optimization, but if speed is super important it's something to keep in mind.
– DIMMSum
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Drop data frame columns by name
...multiple variables:
within(df, rm(x, y))
Or if you're dealing with data.tables (per How do you delete a column by name in data.table?):
dt[, x := NULL] # Deletes column x by reference instantly.
dt[, !"x"] # Selects all but x into a new data.table.
or for multiple variables
dt[, c("x","y...
SQL WITH clause example [duplicate]
...me assigned to the sub-query is treated as though it was an inline view or table. The SQL WITH clause is basically a drop-in replacement to the normal sub-query.
Syntax For The SQL WITH Clause
The following is the syntax of the SQL WITH clause when using a single sub-query alias.
WITH <alias_n...
Discuz! X3 论坛标题字数突破80的限制 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...你的表的前缀，还有修改前一定要备份！！！）
ALTER TABLE `pre_forum_post` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_rsscache` CHANGE `subject` `subject` varchar(255) NOT NULL;
ALTER TABLE `pre_forum_thread` CHANGE `subject` `subject` varchar(255...
Download file of any type in Asp.Net MVC using FileResult?
... @MohammedNoureldin it is not "figuring" it, there is a simple mapping table based on file extensions or something like that. The server does it for all static files, it is not slow.
– Al Kepp
Jul 26 '19 at 9:59
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