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How to use a variable to specify column name in ggplot
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"cumbersome"? Non-standard evaluation in R is ironically the most cumbersome "feature" I have ever encountered in a programming language. Truly maddening.
– jessexknight
Feb 4 at 18:10
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Getting a random value from a JavaScript array
... @SapphireSun this is correct. Note the Math.floor(Math.random(...)) call, which rounds down.
– ashes999
Jan 19 '14 at 12:43
34
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mysql check collation of a table
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The above answer is great, but it doesn't actually provide an example that saves the user from having to look up the syntax:
show table status like 'test';
Where test is the table name.
(Corrected as per comments below.)
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How to validate a url in Python? (Malformed or not)
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Actually, I think this is the best way.
from django.core.validators import URLValidator
from django.core.exceptions import ValidationError
val = URLValidator(verify_exists=False)
try:
val('http://www.google.com')
except Val...
How to list variables declared in script in bash?
... I have to make something to save them to file.
My question is how to list all variables declared in my script and get list like this:
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Why do we need C Unions?
...le types together:
enum Type { INTS, FLOATS, DOUBLE };
struct S
{
Type s_type;
union
{
int s_ints[2];
float s_floats[2];
double s_double;
};
};
void do_something(struct S *s)
{
switch(s->s_type)
{
case INTS: // do something with s->s_ints
break;
case F...
How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...
Recommended date format for REST GET API
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REST doesn't have a recommended date format. Really it boils down to what works best for your end user and your system. Personally, I would want to stick to a standard like you have for ISO 8601 (url encoded).
If not having ugly URI is a concern (e.g. not including th...
How to recover a dropped stash in Git?
... review yesterday's stashed changes, but git stash pop appears to remove all references to the associated commit.
19 Answ...
What is the difference between `after_create` and `after_save` and when to use which?
... readers should note that, according to the docs, ActiveRecord's update_all does not invoke any callbacks, including after_*
– user2426679
Jan 10 at 19:34
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