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R memory management / cannot allocate vector of size n Mb
...ly, or can the matrix be sparse? There is good support in R (see Matrix package for e.g.) for sparse matrices.
Keep all other processes and objects in R to a minimum when you need to make objects of this size. Use gc() to clear now unused memory, or, better only create the object you need in one s...
Change values while iterating
...lue for arrays/slices, which effectively means that the
value is copied, making the original value untouchable.
This behavior is demonstrated by the following code:
x := make([]int, 3)
x[0], x[1], x[2] = 1, 2, 3
for i, val := range x {
println(&x[i], "vs.", &val)
}
The code prints ...
How to remove non-alphanumeric characters?
...
Sounds like you almost knew what you wanted to do already, you basically defined it as a regex.
preg_replace("/[^A-Za-z0-9 ]/", '', $string);
share
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Javascript: formatting a rounded number to N decimals
...ript, the typical way to round a number to N decimal places is something like:
9 Answers
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Where can I find documentation on formatting a date in JavaScript?
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I love 10 ways to format time and date using JavaScript and Working with Dates.
Basically, you have three methods and you have to combine the strings for yourself:
getDate() // Returns the date
getMonth() // Returns the month
getFullYear() // Returns the year
Example:
var d = ne...
Restore file from old commit in git
I have an old commit that I did a few weeks ago. I want to restore only a single file from that commit. What do I do?
4 Ans...
How to access the last value in a vector?
... a vector that is nested in a dataframe one or two levels. Is there a quick and dirty way to access the last value, without using the length() function? Something ala PERL's $# special var?
...
Queue.Queue vs. collections.deque
...s simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas collections.deque doesn't. Queue.Queue isn't intended to be used as a collection, which is why it lacks the likes of the in operator.
It boils down to this: if you have mult...
Viewing unpushed Git commits
...
Epeli
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answered Jan 6 '10 at 22:50
Peter BPeter B
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How to change the type of a field?
...date on the data where the data has the correct type.
In this case, it looks like you're trying to change the $type from 1 (double) to 2 (string).
So simply load the document from the DB, perform the cast (new String(x)) and then save the document again.
If you need to do this programmatically an...