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Does R have an assert statement as in python?
...ndition that will throw an error in your program. Here's an example:
Less_Than_8 = function(x) return(x < 8)
for (i in 1:10)
{
print(i)
stopifnot(Less_Than_8(i))
}
This will print the numbers 1 through 8, then print a message that says
Error: Less_Than_8(i) is not TRUE
It would be ni...
Why am I getting an Exception with the message “Invalid setup on a non-virtual (overridable in VB) m
...ethods and sealed classes. While running a test using mock object, MOQ actually creates an in-memory proxy type which inherits from your "XmlCupboardAccess" and overrides the behaviors that you have set up in the "SetUp" method. And as you know in C#, you can override something only if it is marked ...
Error: Could not find or load main class in intelliJ IDE
...ginner in Java and am trying to run my code using IntelliJ that I just installed as my IDE with JDK 1.7. The following piece of code keeps does not even compile and keeps giving me the error:
...
Pandas aggregate count distinct
...
How about either of:
>>> df
date duration user_id
0 2013-04-01 30 0001
1 2013-04-01 15 0001
2 2013-04-01 20 0002
3 2013-04-02 15 0002
4 2013-04-02 30 0002
>>> df.groupby("date").agg({"duration": np.sum, "use...
How to fix 'sudo: no tty present and no askpass program specified' error?
...type:
sudo visudo
Then edit that file to add to the very end:
username ALL = NOPASSWD: /fullpath/to/command, /fullpath/to/othercommand
eg
john ALL = NOPASSWD: /sbin/poweroff, /sbin/start, /sbin/stop
will allow user john to sudo poweroff, start and stop without being prompted for password.
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How to replace a string in a SQL Server Table Column
...
I'd typically add where path like '%oldstring%' if there was a lot of data.
– Derek Tomes
Nov 2 '15 at 20:48
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What is the best django model field to use to represent a US dollar amount?
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I think this example is correct almost to all currencies. To represent currencies as Bitcoin, I think is much better to use an integer field to save the amount in satoshis, and then show it to the final user in the representation that you want (BTC, mBTC, etc)
...
Find duplicate lines in a file and count how many time each line was duplicated?
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This is what I do however algorithmically this is doesnt seem to be the most efficient approach (O(n log n)*avg_line_len where n is number of lines). I'm working on files that are several gigabytes large, so performance is a key issue. I wonder whether there is ...
How to tell git to ignore individual lines, i.e. gitignore for specific lines of code [duplicate]
...o be filtered:
*.rb filter=gitignore, i.e. run filter named gitignore on all *.rb files
Define the gitignore filter in your gitconfig:
$ git config --global filter.gitignore.clean "sed '/#gitignore$/d'", i.e. delete these lines
$ git config --global filter.gitignore.smudge cat, i.e. do nothing ...
std::shared_ptr thread safety explained
...ly regarding your original 3 questions.
But the ending part of your edit
Calling reset() in thread IV will delete previous instance of A class created in first thread and replace it with new instance? Moreover after calling reset() in IV thread other threads will see only newly created object?
is ...