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How to drop columns by name in a data frame
...hich(names(dat) %in% c("foo","bar"))] ## deletes all columns! Probably not what you wanted...
Instead use subset or the ! function:
dat[ , !names(dat) %in% c("z","u")] ## works as expected
dat[ , !names(dat) %in% c("foo","bar")] ## returns the un-altered data.frame. Probably what you want
I hav...
Set a cookie to never expire
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While that isn't exactly possible you could do something similar to what Google does and set your cookie to expire Jan 17, 2038 or something equally far off.
In all practicality you might be better off setting your cookie for 10 years or 60*60*24*365*10, which should outlive most of the mac...
Sort a Map by values
... Just in case it's not clear to people: this solution will probably not do what you want if you have multiple keys mapping to the same value -- only one of those keys will appear in the sorted result.
– Maxy-B
Nov 24 '11 at 4:37
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String concatenation vs. string substitution in Python
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What you want to concatenate/interpolate and how you want to format the result should drive your decision.
String interpolation allows you to easily add formatting. In fact, your string interpolation version doesn't do th...
How to get the last N records in mongodb?
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What ever it is, the order of calling functions should have nothing to do with the end result.
– Morteza Milani
Mar 9 '12 at 9:21
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Git SSH error: “Connect to host: Bad file number”
...vant.
If you focus on it you'll waste your time as it is not a hint about what the actual problem is, just an effect of running git's ssh on Windows. It's not even a sign that the git or ssh install or configuration is wrong. Really, ignore it.
The very same command on Linux produced instead thi...
Moving decimal places over in a double
...mount of rounding on your behalf, but it is not much. If you are wondering what it might look like without rounding:
System.out.println(new BigDecimal(0.1));
System.out.println(new BigDecimal(x));
prints:
0.100000000000000005551115123125782702118158340454101562
12.3399999999999998578914528479799...
Can I split an already split hunk with git?
...nks by hitting the s key, which adds to the precision of the commit.
But what if I want even more precision, if the split hunk is not small enough?
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How to build a jar using maven, ignoring test results? [duplicate]
... phase. No it doesn't!. You can't skip a phase by using a system property. What it does is set a flag that skips execution of the surefire:test mojo and the compiler:test-compile mojo (possibly others) : maven.apache.org/plugins/maven-surefire-plugin/… maven.apache.org/plugins/maven-compiler-plugi...
convert ArrayList to JSONArray
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That got me close, but what happened was that the toString() output from each object was inserted into the JSONArray as a String. I still ended up with an JSONArray of Strings and not Objects. I ended up creating a method on my class called getJS...