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How to delete multiple values from a vector?
I have a vector like: a = c(1:10) and I need to remove multiple values, like: 2, 3, 5
8 Answers
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JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
15
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How do I convert a String object into a Hash object?
...en its string representation is "{:a=>#<Object:0x7f66b65cf4d0>}", and I can't use eval to turn it back into a hash because #<Object:0x7f66b65cf4d0> isn't valid Ruby syntax.
However, if all that's in the hash is strings, symbols, numbers, and arrays, it should work, because those have...
Wget output document and headers to STDOUT
I'm trying to output document body and its headers to stdout with wget by wget -S -O - http://google.com
5 Answers
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SVN checkout ignore folder
...rsion/project/trunk my_checkout --depth immediates
This will check files and directories from your project trunk into 'my_checkout', but not recurse into those directories. Eg:
$ cd my_checkout && ls
bar/ baz foo xyzzy/
Then to get the contents of 'bar' down:
$ cd bar && svn u...
When to use actors instead of messaging solutions such as WebSphere MQ or Tibco Rendezvous?
I've already read the question and answers to What design decisions would favour Scala's Actors instead of JMS? .
3 Answer...
Confused about stdin, stdout and stderr?
I am rather confused with the purpose of these three files. If my understanding is correct, stdin is the file in which a program writes into its requests to run a task in the process, stdout is the file into which the kernel writes its output and the process requesting it accesses the informatio...
Android destroying activities, killing processes
Hi I'm wondering how Android is managing memory and I can't find precise answer anywhere.
Let's assume I have an application with 5 activities on current activity stack (4 are stopped and 1 is resumed), there is no service connected. I press HOME button so that all of my activities are stopped.
I st...
mongodb: insert if not exists
...-find-else-update block entirely. It will insert if the key doesn't exist and will update if it does.
Before:
{"key":"value", "key2":"Ohai."}
After:
{"key":"value", "key2":"value2", "key3":"value3"}
You can also specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now yo...
How to calculate the number of days between two dates? [duplicate]
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I tested this with 2015-02-1 to 2015-03-01 and got 31 days. There's something wrong here... EDIT: Okay yeah.. javascript months are from 0-12 so if you're getting the input from a jquery datepicker or a regular normal date, subtract 1 form the month
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