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How to find the length of a string in R
... @hadley Indeed, or for that matter any character vector with one or more NAs. (Though this is documented to be so).
– Gavin Simpson
Mar 19 '14 at 16:19
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Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...
I would recommend to debug and find which constraint is "the one you don't want". Suppose you have following issue:
Always the problem is how to find following Constraints and Views.
There are two solutions how to do this:
DEBUG VIEW HIERARCHY (Do not recommend this way)
Since ...
Can I export a variable to the environment from a bash script without sourcing it?
...answer: No.
But there are several possible workarounds.
The most obvious one, which you've already mentioned, is to use source or . to execute the script in the context of the calling shell:
$ cat set-vars1.sh
export FOO=BAR
$ . set-vars1.sh
$ echo $FOO
BAR
Another way is to have the script, ...
Execute a command line binary with Node.js
... don't want to put everything into a file, but I want to execute more than one command? Maybe like echo "hello" and echo "world".
– Cameron
May 24 '17 at 15:24
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Why are Docker container images so large?
...ant to note that the base images (like fedora:latest tend to be very bare-bones. You may be surprised by the number of dependencies your installed software has.
I was able to make your installation significantly smaller by adding yum -y clean all to each line:
FROM fedora:latest
RUN yum -y install...
How to click first link in list of items after upgrading to Capybara 2.0?
...nt is that xpath can address an array of matches and pull out a particular one. You should be able to match with this.
A working example example from one of my projects:
within page.find("div.panel", text: /Proposals/) do
within page.find('tr', text: /Foo/) do
page.should have_xpath('td[3]...
How can I pass arguments to a batch file?
...ent"? Then, if you don't have an answer, you should use a trick like the one of the dots. Remember that, like stated here ss64.com/nt/if.html "You can in fact use almost any character for this a '~' or curly brackets, { } or even the number 4, but square brackets tend to be chosen because they do...
junit & java : testing non-public methods [duplicate]
...ose methods in my class that are public. How do I do junit testing on the ones that are not (i.e., private, protected)?
...
Why should I use Google's CDN for jQuery?
... I love how you keep coming up with more and more reasons. +1 for that alone.
– Matchu
Feb 1 '10 at 22:10
6. Googles...
In Python, when to use a Dictionary, List or Set?
...ent more than once, can be found in collections.Counter -- you could build one as a dict, if for some weird reason you couldn't import collections, or, in pre-2.7 Python as a collections.defaultdict(int), using the items as keys and the associated value as the count).
Checking for membership of a v...