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Why are my basic Heroku apps taking two seconds to load?
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If your application is unused for a while it gets unloaded (from the server memory).
On the first hit it gets loaded and stays loaded until some time passes without anyone accessing it.
This is done to save server resources. If no one uses your app why keep resources busy and not...
What's the difference between “mod” and “remainder”?
...nteger type. C11dr §6.5.5 2
The result of the / operator is the quotient from the division of the first operand by the second; the result of the % operator is the remainder ... C11dr §6.5.5 5
What's the difference between “mod” and “remainder”?
C does not define "mod", such as the in...
Core Data vs SQLite 3 [closed]
...ng forward and backward links consistent when objects are added/removed to/from a relationship). Core Data is thus an ideal framework for building the "model" component of an MVC architecture.
To implement its graph management, Core Data happens to use SQLite as a disk store. It could have been imp...
Constant pointer vs Pointer to constant [duplicate]
... the declaration like this which make it easy to read and understand (read from right to left):
int const *ptr; // ptr is a pointer to constant int
int *const ptr; // ptr is a constant pointer to int
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What's the difference between belongs_to and has_one?
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That is pretty much the same the accepted answer from two years ago already states.
– matthias krull
Oct 5 '12 at 18:26
11
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How to detect UI thread on Android?
....currentThread()) {
// On UI thread.
} else {
// Not on UI thread.
}
From API level 23 and up, there's a slightly more readable approach using new helper method isCurrentThread on the main looper:
if (Looper.getMainLooper().isCurrentThread()) {
// On UI thread.
} else {
// Not on UI threa...
Deleting a resource using http DELETE
... all these debates. But that specs has been superseded by RFC 7231. Quoted from RFC 7231, section 4.2.2 Idempotent Methods, emphasis mine:
A request method is considered "idempotent" if the intended EFFECT ON
THE SERVER of multiple identical requests with that method is the
same as the effec...
git - Find commit where file was added
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How does this work on files that are merged from other branches, but which weren't necessarily added to the branch being merged by the user performing the merge?
– g33kz0r
Jan 22 '14 at 18:47
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adding noise to a signal in python
...rmal(0,1,100)
# 0 is the mean of the normal distribution you are choosing from
# 1 is the standard deviation of the normal distribution
# 100 is the number of elements you get in array noise
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Pandas percentage of total with groupby
... the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.rand...