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Is there an R function for finding the index of an element in a vector?
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@John : that's all true, but that is not what the OP asked. The OP asked, starting from a long vector, to find the first match of elements given in another one. And for completeness, I added that if you are interested in all indices, you'll...
How ListView's recycling mechanism works
So I have this problem I had before, and naturally I asked for help on here . Luksprog's answer was great because I had no idea about how ListView and GridView optimized itself with recycling Views. So with his advice I was able to change how I added Views to my GridView. Problem is now I have some...
How should strace be used?
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Strace Overview
strace can be seen as a light weight debugger. It allows a programmer / user to quickly find out how a program is interacting with the OS. It does this by monitoring system calls and signals.
Uses
Good for when you don't have source code or don't want to be bothered to real...
How to avoid using Select in Excel VBA
...hortcut to the Evaluate method, but this is less efficient and should generally be avoided in production code.
Set rng = [A1]
Set rng = [A1:B10]
All the above examples refer to cells on the active sheet. Unless you specifically want to work only with the active sheet, it is better to Dim a Works...
Set value of hidden field in a form using jQuery's “.val()” doesn't work
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Andy, thanks for the quick response. I actually tried with the "#texens" first, and then with "#input:hidden#texens" and neither of them seemed to work. When I changed the input type in the form from "hidden" to "text", and "#input:hidden:texens" to "#input:text:tex...
mongo - couldn't connect to server 127.0.0.1:27017
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Normally this caused because you didn't start mongod process before you try starting mongo shell.
Start mongod server
mongod
Open another terminal window
Start mongo shell
mongo
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Heroku “psql: FATAL: remaining connection slots are reserved for non-replication superuser connectio
I'm developing an app on Heroku with a Postgresql backend. Periodically, I get this error message when trying to access the database, both from the CLI and from loading a page on the server:
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What is the difference between float and double?
...i.e. using one or the other does not seem to affect the results. Is this really the case? When are floats and doubles interchangeable? What are the differences between them?
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Why is 128==128 false but 127==127 is true when comparing Integer wrappers in Java?
...ertain numbers are "pooled", and it returns the same instance for values smaller than 128.
From the java 1.6 source code, line 621:
public static Integer valueOf(int i) {
if(i >= -128 && i <= IntegerCache.high)
return IntegerCache.cache[i + 128];
else
return n...
How to detect when an Android app goes to the background and come back to the foreground
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The onPause() and onResume() methods are called when the application is brought to the background and into the foreground again. However, they are also called when the application is started for the first time and before it is killed. You can read more in Activity.
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