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Speed up the loop operation in R
...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,].
Try to avoid this as much as possible. I took your function, change indexing and here version_A
dayloop2_A <- function(temp){
res <- numeric(nrow(temp))
for (i in 1:nrow(te...
How do you round a number to two decimal places in C#?
...ults to MidPointRounding.ToEven (aka "Bankers Rounding") is because the we all learned to round in school where .5 rounds up causes too much rounding up. This is a problem when dealing with money, tax calculations, etc.
– asporter
Nov 11 '16 at 19:36
...
NoSQL (MongoDB) vs Lucene (or Solr) as your database
...arned:
You can easily use Lucene/Solr in lieu of MongoDB for pretty much all situations, but not vice versa. Grant Ingersoll's post sums it up here.
MongoDB etc. seem to serve a purpose where there is no requirement of searching and/or faceting. It appears to be a simpler and arguably easier trans...
Export Data from mysql Workbench 6.0
...Windows: C:\Program Files\MySQL\MySQL Workbench 6.3 CE\modules (32-bit installation on x64 systems: C:\Program Files (x86)\MySQL\MySQL Workbench 6.3 CE\modules)
b) Mac OS X: Applications/MYSQLWorkbench.app/Contents/Resources/plugins - right click on the app and select Show Package contents to get i...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
... mapping.
You would need to know the length of the substring that was actually matched. But Compare, IndexOf ..etc
throw that information away. It could be possible with regular expressions but the implementation doesn't do full case folding and so doesn't match
ß to ss/SS in case-insensitive mode...
See :hover state in Chrome Developer Tools
...t not if you make changes onhover using JS.
– matthew_360
Feb 6 '15 at 16:31
Here's a quick video I threw together dem...
How to drop SQL default constraint without knowing its name?
...llowing script will generate the command to drop the constraint and dynamically execute it.
declare @schema_name nvarchar(256)
declare @table_name nvarchar(256)
declare @col_name nvarchar(256)
declare @Command nvarchar(1000)
set @schema_name = N'MySchema'
set @table_name = N'Department'
set @col_...
Installing R on Mac - Warning messages: Setting LC_CTYPE failed, using “C”
I would like install R on my laptop Mac OS X version 10.7.3
6 Answers
6
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Equivalent of jQuery .hide() to set visibility: hidden
...n example on how to support additional parameters of show (speed, easing, callback)?
– georg
Mar 8 '12 at 8:57
11
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How is mime type of an uploaded file determined by browser?
...dden), and then if not found there, we defer to the system registry.
// Finally, we scan a secondary hard-coded list to catch types that we can
// deduce but that we also want to allow the OS to override.
The hard-coded lists come a bit earlier in the file: https://cs.chromium.org/chromium/src/net/...