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How to rename a single column in a data.frame?
...r.name'
This code pretty much does the following:
names(df) looks into all the names in the df
[names(df) == old.var.name] extracts the variable name you want to check
<- 'new.var.name' assigns the new variable name.
...
Why aren't variables declared in “try” in scope in “catch” or “finally”?
...Reader sr,
[1] class [mscorlib]System.Exception ex)
IL_0000: ldnull
IL_0001: stloc.0
.try
{
.try
{
IL_0002: ldsfld string UsingTest.Class1::path
IL_0007: newobj instance void [mscorlib]System.IO.StreamReader::.cto...
Reintegrate can only be used if revisions X through Y were previously merged from to reintegra
Been using SVN branches with Tortoise 1.6. I've been periodically merging the trunk into the branch to keep it up to date.
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Code for Greatest Common Divisor in Python [closed]
... the result will have the same sign as b", hence gcd(1, -1) == -1 seems totally legit to me.
– Marco Bonelli
Jan 11 '15 at 2:30
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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
How can you get the Manifest Version number from the App's (Layout) XML variables?
...ntext.getPackageName(), 0).versionName;
Either of these solutions would allow for placing the version name in XML. Unfortunately there isn't a nice simple solution, like android.R.string.version or something like that.
sh...
receiving error: 'Error: SSL Error: SELF_SIGNED_CERT_IN_CHAIN' while using npm
... on ubuntu - I am receiving the error copied below while attempting to install any new modules via npm (I tested socket.io earlier using http, not https though & am wondering if that could have resulted in the issue with npm/unsigned certs). The error pops up once npm tries to resolve the ' https:/...
How do I add the contents of an iterable to a set?
What is the "one [...] obvious way" to add all items of an iterable to an existing set ?
6 Answers
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How to set radio button checked as default in radiogroup?
I have created RadioGroup and RadioButton dynamically as following:
8 Answers
8
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MySQL - UPDATE query based on SELECT Query
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You can actually do this one of two ways:
MySQL update join syntax:
UPDATE tableA a
INNER JOIN tableB b ON a.name_a = b.name_b
SET validation_check = if(start_dts > end_dts, 'VALID', '')
-- where clause can go here
ANSI SQL syntax...