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Extract a dplyr tbl column as a vector
...ge:base':
#>
#> intersect, setdiff, setequal, union
db <- src_sqlite(tempfile(), create = TRUE)
iris2 <- copy_to(db, iris)
vec <- pull(iris2, Species)
head(vec)
#> [1] "setosa" "setosa" "setosa" "setosa" "setosa" "setosa"
...
How do I pass the value (not the reference) of a JS variable to a function? [duplicate]
...esults[i];
google.maps.event.addListener(marker, 'click', () => change_selection(i));
}
In older browsers, you need to create a separate scope that saves the variable in its current state by passing it as a function parameter:
for (var i = 0; i < results.length; i++) {
(function (i) ...
How to check if the URL contains a given string?
...
I have a long URL like this, preview.tbwabox.co.nz/_v005/index.html#buying-a-car and I want to check if the string has "buying-a-car but the script" isn't working?
– Vennsoh
Jul 9 '15 at 2:16
...
Android SDK on a 64-bit linux machine
...s. Your solution worked for my Linux Mint 13.
– pavel_kazlou
Sep 20 '12 at 20:55
Agree with commenter above, ubuntu 12...
Replace a string in shell script using a variable
...x> echo X123456789X | sed "s/123456789/${replace}/"
X987654321X
pax> _
Just be careful to ensure that ${replace} doesn't have any characters of significance to sed (like / for instance) since it will cause confusion unless escaped. But if, as you say, you're replacing one number with another...
In MVVM should the ViewModel or Model implement INotifyPropertyChanged?
...t lives in the System.ComponentModel namespace, I have used it in WinForms applications, also INotifyPropertyChanged has been in .Net since 2.0, WPF has only been around since 3.0
– benPearce
Mar 4 '11 at 6:03
...
How to create PDF files in Python [closed]
...th the style and markup you want for you pdf document
Executing pdfkit.from_string(...) method by passing the rendered html as parameter
This way you get a pdf document with styling and images supported.
You can install it as follows :
using pip
pip install pdfkit
You will also need to instal...
Is mathematics necessary for programming? [closed]
I happened to debate with a friend during college days whether advanced mathematics is necessary for any veteran programmer. He used to argue fiercely against that. He said that programmers need only basic mathematical knowledge from high school or fresh year college math, no more no less, and that ...
iOS Detect 3G or WiFi
...TelephonyNetworkInfo *netinfo = [[CTTelephonyNetworkInfo alloc] init];
_carrier = [[netinfo subscriberCellularProvider] carrierName];
if ([netinfo.currentRadioAccessTechnology isEqualToString:CTRadioAccessTechnologyGPRS]) {
NSLog(@"2G");
} else if ([netinfo.currentRadioAccessTec...
What is the reason not to use select *?
... join
The corollary is that using select * ...
The columns used by the application is opaque
DBA's and their query profilers are unable to help your application's poor performance
The code is more brittle when changes occur
Your database and network are suffering because they are bringing back t...