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How do I replace NA values with zeros in an R dataframe?
... mutate(myCol1 = if_else(is.na(myCol1), 0, myCol1))
Note: This works per selected column, if we need to do this for all column, see @reidjax's answer using mutate_each.
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How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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Is there a way to create multiline comments in Python?
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In any case, your text editor should also be able to easily comment-out a selected region (by placing a # in front of each line individually). If not, switch to a text editor that does.
Programming in Python without certain text editing features can be a painful experience. Finding the right edito...
MySQL DISTINCT on a GROUP_CONCAT()
I am doing SELECT GROUP_CONCAT(categories SEPARATOR ' ') FROM table . Sample data below:
6 Answers
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Best GWT widget library? [closed]
...nd it
LOTS of examples online, all of which have accompanying code
Good selection of widgets that cover a wide range of functionality
Cons:
Makes assumptions about your data's format and structure that you may not be able to accommodate
Library is just a JSNI wrapper, which makes it harder to...
Visual Studio appears to randomly adopt American keyboard layout
...new Settings app, but there's also an option in the old Region Settings to select a Region for apps that don't support Unicode. For me, this was set to English (UK) even though my only display language is English (Australia).
– rensa
Jul 2 '18 at 4:11
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MySQL dump by query
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not mysqldump, but mysql cli...
mysql -e "select * from myTable" -u myuser -pxxxxxxxxx mydatabase
you can redirect it out to a file if you want :
mysql -e "select * from myTable" -u myuser -pxxxxxxxx mydatabase > mydumpfile.txt
Update:
Original post asked if...
Export to CSV via PHP
...ion: close");
}
function getSql()
{
// return you own sql
$sql = "SELECT id, date, params, value FROM sometable ORDER BY date;";
return $sql;
}
function getExportData()
{
$values = array();
$sql = $this->getSql();
if (strlen($sql) > 0)
{
$result = dbquery...
What is the best way to filter a Java Collection?
...without writing loops or inner classes:
List<Person> beerDrinkers = select(persons, having(on(Person.class).getAge(),
greaterThan(16)));
Can you imagine something more readable?
Disclaimer: I am a contributor on lambdaj
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Fragment onCreateView and onActivityCreated called twice
....getFragmentManager().findFragmentByTag(mTag);
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.replace(android.R.id.content, mFragment, mTag);
} ...