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Scraping html tables into R data frames using the XML package
...t)
theurl <- getURL("https://en.wikipedia.org/wiki/Brazil_national_football_team",.opts = list(ssl.verifypeer = FALSE) )
tables <- readHTMLTable(theurl)
tables <- list.clean(tables, fun = is.null, recursive = FALSE)
n.rows <- unlist(lapply(tables, function(t) dim(t)[1]))
the picked tab...
Split delimited strings in a column and insert as new rows [duplicate]
I have a data frame as follow:
6 Answers
6
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How to add Google Analytics Tracking ID to GitHub Pages
... I have added them, however Google analytics say the Tracking is not installed. My page as specified in G-Analytics is http://avi-aryan.github.io
– Avi
Jul 15 '13 at 12:33
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What columns generally make good indexes?
...ng to learn about indexes, what columns are good index candidates? Specifically for an MS SQL database?
12 Answers
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mysql -> insert into tbl (select from another table) and some default values [duplicate]
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If you want to insert all the columns then
insert into def select * from abc;
here the number of columns in def should be equal to abc.
if you want to insert the subsets of columns then
insert into def (col1,col2, col3 ) select scol1,scol2,...
Rails Migration: Remove constraint
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ndnenkov
32.3k99 gold badges6060 silver badges9090 bronze badges
answered Jan 31 '14 at 6:49
deepakdeepak
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Location of parenthesis for auto-executing anonymous JavaScript functions?
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They're virtually the same.
The first wraps parentheses around a function to make it a valid expression and invokes it. The result of the expression is undefined.
The second executes the function and the parentheses around the automati...
Random record from MongoDB
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Do a count of all records, generate a random number between 0 and the count, and then do:
db.yourCollection.find().limit(-1).skip(yourRandomNumber).next()
share
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How to turn on/off ReactJS 'development mode'?
...me helpers off during production. Just using the minified react will leave all those potential optimizations on the table as well.
Ultimately the magic comes down to React embedding references to process.env.NODE_ENV throughout the codebase; these act like a feature toggle.
if (process.env.NODE_ENV ...
PDO Prepared Inserts multiple rows in single query
... table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
if($count > 0){
for($x=0; $x<$count; $x++){
$re...