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Easier way to populate a list with integers in .NET [duplicate]
... numbers = Enumerable.Range(from, end - from + 1)
.Select(n => f(n))
.ToList();
For example:
var primes = Enumerable.Range(1, 10)
.Select(n => Prime(n))
.ToList();
would generate the first ten pr...
Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
...heck your database transaction isolation level in the mysql cli:
mysql> SELECT @@GLOBAL.tx_isolation, @@tx_isolation, @@session.tx_isolation;
+-----------------------+-----------------+------------------------+
| @@GLOBAL.tx_isolation | @@tx_isolation | @@session.tx_isolation |
+----------------...
Apply multiple functions to multiple groupby columns
... group. When aggregating, g will be a Series. Passing g.index to df.ix[] selects the current group from df. I then test if column C is less than 0.5. The returned boolean series is passed to g[] which selects only those rows meeting the criteria.
In [95]: cust = lambda g: g[df.loc[g.index]['C']...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...f these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.
For more guidance on this, see:
:help :map
:help :noremap
:help recursi...
How to change folder with git bash?
...
Go to the directory manually and do right click → Select 'Git bash' option.
Git bash terminal automatically opens with the intended directory. For example, go to your project folder. While in the folder, right click and select the option and 'Git bash'. It will open automat...
Similar to jQuery .closest() but traversing descendants?
...
These examples all select depth-first descendants, not breadth-first, so these can't be used to solve the original question. In my testing they all returned the first span, not the second.
– JrBaconCheez
M...
Are database triggers evil? [closed]
...lumns wouldn't exist and you'd have to process a function on each row when selecting them. That's likely to kill DBMS performance, far better to create the auto-generated column at insert/update time since that's the only time it changes.
Also, lack of triggers would prevent data rules from being e...
what is reverse() in Django
... question = get_object_or_404(Question, pk=question_id)
try:
selected = question.choice_set.get(pk=request.POST['choice'])
except KeyError:
# handle exception
pass
else:
selected.votes += 1
selected.save()
return HttpResponseRedirect(reve...
How do I update a Linq to SQL dbml file?
... was getting 'Specified cast is not valid' errors when performing a simple select on a view. Including 1b fixed it for me
– tomfumb
Nov 29 '11 at 19:40
6
...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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