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Expert R users, what's in your .Rprofile? [closed]
...se it might breaks my coauthors' code, I wish it was the default. Why?
1) Character vectors use less memory (but only barely);
2) More importantly, we would avoid problems such as:
> x <- factor(c("a","b","c"))
> x
[1] a b c
Levels: a b c
> x <- c(x, "d")
> x
[1] "1" "2" "3" "...
Row count with PDO
...
$sql = "SELECT count(*) FROM `table` WHERE foo = ?";
$result = $con->prepare($sql);
$result->execute([$bar]);
$number_of_rows = $result->fetchColumn();
Not the most elegant way to do it, plus it involves an extra query...
How can I combine multiple rows into a comma-delimited list in Oracle? [duplicate]
...countries values ('Andorra');
insert into countries values ('Antigua');
SELECT SUBSTR (SYS_CONNECT_BY_PATH (country_name , ','), 2) csv
FROM (SELECT country_name , ROW_NUMBER () OVER (ORDER BY country_name ) rn,
COUNT (*) OVER () cnt
FROM countries)
WHE...
How do I list all tables in a schema in Oracle SQL?
... schema, you need to have one or more of the following system privileges:
SELECT ANY DICTIONARY
(SELECT | INSERT | UPDATE | DELETE) ANY TABLE
or the big-hammer, the DBA role.
With any of those, you can select:
SELECT DISTINCT OWNER, OBJECT_NAME
FROM DBA_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
...
ng-options with simple array init
...
You actually had it correct in your third attempt.
<select ng-model="myselect" ng-options="o as o for o in options"></select>
See a working example here:
http://plnkr.co/edit/xEERH2zDQ5mPXt9qCl6k?p=preview
The trick is that AngularJS writes the keys as numbers from...
Selecting/excluding sets of columns in pandas [duplicate]
...e to create views or dataframes from an existing dataframe based on column selections.
9 Answers
...
Pipe to/from the clipboard in Bash script
...lets you talk to it.
In the case of X, there's xclip (and others). xclip -selection c will send data to the clipboard that works with Ctrl + C, Ctrl + V in most applications.
If you're on Mac OS X, there's pbcopy. e.g cat example.txt | pbcopy
If you're in Linux terminal mode (no X) then look into...
How do I find numeric columns in Pandas?
...
You could use select_dtypes method of DataFrame. It includes two parameters include and exclude. So isNumeric would look like:
numerics = ['int16', 'int32', 'int64', 'float16', 'float32', 'float64']
newdf = df.select_dtypes(include=numer...
How can I read large text files in Python, line by line, without loading it into memory?
...in sensible sized chunks (kilobytes to megabytes say) and split on newline characters ( or whatever the line ending char is on your platform)
– John La Rooy
Jun 25 '11 at 2:36
4
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How do I iterate through the alphabet?
In Python, could I simply ++ a char? What is an efficient way of doing this?
2 Answers
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