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How to do joins in LINQ on multiple fields in single join
... work fine. LINQ can only represent equijoins (with join clauses, anyway), and indeed that's what you've said you want to express anyway based on your original query.
If you don't like the version with the anonymous type for some specific reason, you should explain that reason.
If you want to do s...
Detect and exclude outliers in Pandas data frame
I have a pandas data frame with few columns.
17 Answers
17
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Iterating through a Collection, avoiding ConcurrentModificationException when removing objects in a
...= new ArrayList<>();
// This is a clever way to create the iterator and call iterator.hasNext() like
// you would do in a while-loop. It would be the same as doing:
// Iterator<String> iterator = list.iterator();
// while (iterator.hasNext()) {
for (Iterator<String> iterat...
Detect if Android device has Internet connection
...
The best way to check if there is an active Internet connection is to try and connect
to a known server via http.
public static boolean hasActiveInternetConnection(Context context) {
if (isNetworkAvailable(context)) {
try {
HttpURLConnection urlc = (HttpURLConnection) (new...
Increment a value in Postgres
... want to take a value (which is an integer) in a field in a postgres table and increment it by one. For example if the table 'totals' had 2 columns, 'name' and 'total', and Bill had a total of 203, what would be the SQL statement I'd use in order to move Bill's total to 204?
...
Check if a folder exist in a directory and create them using C#
How can I check if directory C:/ contains a folder named MP_Upload , and if it does not exist, create the folder automatically?
...
Why doesn't java.lang.Number implement Comparable? [duplicate]
...itive types (float, double), determining if two values are equal is tricky and has to be done within an acceptable margin of error. Try code like:
double d1 = 1.0d;
double d2 = 0.0d;
for (int i=0; i<10; i++) {
d2 += 0.1d;
}
System.out.println(d2 - d1);
and you'll be left with some small dif...
Get OS-level system information
... run on many different platforms, but primarily variants of Solaris, Linux and Windows.
16 Answers
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Compiler error: memset was not declared in this scope
...t a problem like this just go to the man page for the function in question and it will tell you what header you are missing, e.g.
$ man memset
MEMSET(3) BSD Library Functions Manual MEMSET(3)
NAME
memset -- fill a byte string with a byte value
LIBRARY
Stan...
NullPointerException in Java with no StackTrace
...interException) occurs for the first time, the full stack trace is printed and the JVM remembers the stack trace (or maybe just the location of the code). When that exception occurs often enough, the stack trace is not printed anymore, both to achieve better performance and not to flood the log with...