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MongoDB SELECT COUNT GROUP BY
...er way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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How do I convert from stringstream to string in C++?
...;
}
For all the methods above, you must include the following two header files.
#include <string>
#include <sstream>
Note that, the argument NumericValue in the examples above can also be passed as std::string or std::wstring to be used with the std::ostringstream and std::wostrings...
how to make svn diff show only non-whitespace line changes between two revisions
...
You can use
svn diff -r 100:200 -x -b > file.diff
If you want to ignore all whitespaces:
svn diff -x -w | less
Source
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How to delete the contents of a folder?
...
import os, shutil
folder = '/path/to/folder'
for filename in os.listdir(folder):
file_path = os.path.join(folder, filename)
try:
if os.path.isfile(file_path) or os.path.islink(file_path):
os.unlink(file_path)
elif os.path.isdir(file_path)...
How to loop through files matching wildcard in batch file
I have a set of base filenames, for each name 'f' there are exactly two files, 'f.in' and 'f.out'. I want to write a batch file (in Windows XP) which goes through all the filenames, for each one it should:
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Rubymine: How to make Git ignore .idea files created by Rubymine
...bymine for Rails projects. Very often, Rubymine makes changes in .idea/* files that I don't care about. But it keeps preventing me from checking out new branches, and makes my version of .idea/ different from my coworkers.
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Get all directories within directory nodejs
...e)).filter(isDirectory)
Update for Node 10.10.0+
We can use the new withFileTypes option of readdirSync to skip the extra lstatSync call:
const { readdirSync } = require('fs')
const getDirectories = source =>
readdirSync(source, { withFileTypes: true })
.filter(dirent => dirent.isDi...
Bundling data files with PyInstaller (--onefile)
I'm trying to build a one-file EXE with PyInstaller which is to include an image and an icon. I cannot for the life of me get it to work with --onefile .
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Get a list of resources from classpath directory
...ement your own scanner. For example:
private List<String> getResourceFiles(String path) throws IOException {
List<String> filenames = new ArrayList<>();
try (
InputStream in = getResourceAsStream(path);
BufferedReader br = new BufferedReader(new Inp...
How to check if a Unix .tar.gz file is a valid file without uncompressing?
I have found the question How to determine if data is valid tar file without a file? , but I was wondering: is there a ready made command line solution?
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