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Split comma-separated strings in a column into separate rows
...blem size `n`
mb_times <- scales::squish(10000L / n , c(3L, 100L))
cat(n, " ", mb_times, "\n")
# create data
DF <- data.frame(director = rep(director, n), AB = rep(AB, n))
DT <- as.data.table(DF)
# start benchmarks
microbenchmark::microbenchmark(
matt_mod = {
s <...
pandas: How do I split text in a column into multiple rows?
...rnative:
time python -c "import pandas as pd;
from scipy import array, concatenate;
df = pd.DataFrame(['a b c']*100000, columns=['col']);
print pd.DataFrame(concatenate(df['col'].apply( lambda x : [x.split(' ')]))).head()"
... and this:
time python -c "import pandas as pd;
df = pd.DataFrame(['a ...
Floating elements within a div, floats outside of div. Why?
...sed certain bits of text to become unreadable.
– Top Cat
Feb 23 '18 at 11:26
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How do I break a string over multiple lines?
...rent/components/yaml/yaml_format.html
You can use the "block chomping indicator" to eliminate the trailing line break, as follows:
Key: >-
This is a very long sentence
that spans several lines in the YAML
but which will be rendered as a string
with NO carriage returns.
There are other...
Parse usable Street Address, City, State, Zip from a string [closed]
...com/send/official-abbreviations.htm
– Mike Sherrill 'Cat Recall'
Jul 26 '11 at 21:48
17
"Only 50"...
Why does changing 0.1f to 0 slow down performance by 10x?
... credits to Carl Hetherington [1])
[1] http://carlh.net/plugins/denormals.php
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Django CharField vs TextField
... answered Sep 8 '11 at 21:23
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How to track down a “double free or corruption” error
... deleting the same entity twice
you are deleting something that wasn't allocated
For the first one I strongly suggest NULL-ing all deleted pointers.
You have three options:
overload new and delete and track the allocations
yes, use gdb -- then you'll get a backtrace from your crash, and that'll...
Why do you need to create a cursor when querying a sqlite database?
...
Cursors can not only be used to fetch data from the DBMS into an
application but also to identify a row in a table to be updated or
deleted. The SQL:2003 standard defines positioned update and
positioned delete SQL statements for that purpose. Such statements do
not use a regular WHERE cl...
What “things” can be injected into others in Angular.js?
... hold of the $provide service by asking for it to be injected into an application's config function. An example might be something like this:
app.config(function($provide) {
$provide.provider('greeting', function() {
this.$get = function() {
return function(name) {
alert("Hello,...