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How to select a CRAN mirror in R
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Repository selection screen cannot be shown on your system (OS X), since OS X no longer includes X11. R tries to show you the prompt through X11. Install X11 from http://xquartz.macosforge.org/landing/. Then run the install command. The...
Best implementation for hashCode method for a collection
...he field f is a boolean:
calculate (f ? 0 : 1);
If the field f is a byte, char, short or int: calculate (int)f;
If the field f is a long: calculate (int)(f ^ (f >>> 32));
If the field f is a float: calculate Float.floatToIntBits(f);
If the field f is a double: calculate Double.doubleToLong...
Convert string[] to int[] in one line of code using LINQ
...you would need the extra ToArray call to get an array:
int[] myInts = arr.Select(int.Parse).ToArray();
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How do you configure an OpenFileDialog to select folders?
In VS .NET, when you are selecting a folder for a project, a dialog that looks like an OpenFileDialog or SaveFileDialog is displayed, but is set up to accept only folders. Ever since I've seen this I've wanted to know how it's done. I am aware of the FolderBrowserDialog, but I've never really like...
How to execute raw SQL in Flask-SQLAlchemy app
...xecute("<sql here>")
or:
from sqlalchemy import text
sql = text('select name from penguins')
result = db.engine.execute(sql)
names = [row[0] for row in result]
print names
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...c
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But what should the value of b show on each of these two rows? There are three possibilities in each case, and no...
What does multicore assembly language look like?
...few tweaks to make it work on gem5, so you can experiment with performance characteristics as well.
I haven't tested it on real hardware, so and I'm not sure how portable this is. The following Raspberry Pi bibliography might be of interest:
https://github.com/bztsrc/raspi3-tutorial/tree/a3f069b7...
Android - Pulling SQlite database android device
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Yes, this is because the / is as special string char. // in your "//" will result in /.
– KarlKarlsom
Apr 4 '12 at 14:36
4
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How to access pandas groupby dataframe by key
...t uses data-structures already available in the groupby object.
You can select different columns using the groupby slicing:
In [22]: gb[["A", "B"]].get_group("foo")
Out[22]:
A B
0 foo 1.624345
2 foo -0.528172
4 foo 0.865408
In [23]: gb["C"].get_group("foo")
Out[23]:
0 5
2 ...
How to ignore SVN folders in WinMerge?
...ersion housekeeping directories
d: \\.svn$
d: \\._svn$
Save it, then when selecting items to merge, select the filter you defined from the Select Files or Folders dialog box. Bonus points: It will save this and use it as a default for future merges.
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