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What's the difference between ASCII and Unicode?
...
ASCII defines 128 characters, which map to the numbers 0–127. Unicode defines (less than) 221 characters, which, similarly, map to numbers 0–221 (though not all numbers are currently assigned, and some are reserved).
Unicode is a superset...
Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
...
How are software license keys generated?
...ype in.
We must be able to blacklist (revoke) a license key in the case of chargebacks or purchases with stolen credit cards.
No “phoning home” to test keys. Although this practice is becoming more and more prevalent, I still do not appreciate it as a user, so will not ask my users to put up wi...
SQL Server String or binary data would be truncated
...ur source query and execute Max(Len( source col )) on each column. I.e.,
Select Max(Len(TextCol1))
, Max(Len(TextCol2))
, Max(Len(TextCol3))
, ...
From ...
Then compare those lengths to the data type lengths in your destination table. At least one, exceeds its destination column leng...
How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails
... write a plugin that would do something like: SampleModel.find(:all, :select => "DISTINCT(*)", :conditions => ["date > #{self.date}"], :limit => 1, :order => 'date', :group => "date").show_generated_sql and have this call the construct_finder_sql method.
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PostgreSQL - Rename database
...res
-- force disconnect all other clients from the database to be renamed
SELECT pg_terminate_backend( pid )
FROM pg_stat_activity
WHERE pid <> pg_backend_pid( )
AND datname = 'name of database';
-- rename the database (it should now have zero clients)
ALTER DATABASE "name of database" R...
How to get the caret column (not pixels) position in a textarea, in characters, from the start?
...refox, Safari (and other Gecko based browsers) you can easily use textarea.selectionStart, but for IE that doesn't work, so you will have to do something like this:
function getCaret(node) {
if (node.selectionStart) {
return node.selectionStart;
} else if (!document.selection) {
return ...
UltiSnips and YouCompleteMe
...
" make YCM compatible with UltiSnips (using supertab)
let g:ycm_key_list_select_completion = ['<C-n>', '<Down>']
let g:ycm_key_list_previous_completion = ['<C-p>', '<Up>']
let g:SuperTabDefaultCompletionType = '<C-n>'
" better key bindings for UltiSnipsExpandTrigger
...
How I can I lazily read multiple JSON values from a file/stream in Python?
... end_pos = int(re.match('Extra data: line \d+ column \d+ .*\(char (\d+).*\)',
e.args[0]).groups()[0])
json_str = f.read(end_pos)
obj = json.loads(json_str)
start_pos += end_pos
yield obj...
Open terminal here in Mac OS finder [closed]
...not just Finder, and they operate on folders as well as absolute pathnames selected in text.
You can even assign command keys to them.
Services appear in the Services submenu of each application menu, and within the contextual menu (Control-Click or Right-Click on a folder or pathname).
The New T...