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Check if an array is empty or exists
...
if (typeof image_array !== 'undefined' && image_array.length > 0) {
// the array is defined and has at least one element
}
Your problem may be happening due to a mix of implicit global variables and variable hoisting. Make sure you use var whenever declaring a variable:
<?php e...
What are “named tuples” in Python?
...xcept that they are immutable. They were added in Python 2.6 and Python 3.0, although there is a recipe for implementation in Python 2.4.
For example, it is common to represent a point as a tuple (x, y). This leads to code like the following:
pt1 = (1.0, 5.0)
pt2 = (2.5, 1.5)
from math import s...
Why does Lua have no “continue” statement?
...Lua 5.2 the best workaround is to use goto:
-- prints odd numbers in [|1,10|]
for i=1,10 do
if i % 2 == 0 then goto continue end
print(i)
::continue::
end
This is supported in LuaJIT since version 2.0.1
share
...
How to connect to Mysql Server inside VirtualBox Vagrant?
... can I connect to that server outside the vm? I already forward the port 3306 of the Vagrantfile , but when I try to connect to the mysql server, it`s resposts with the error:
'reading initial communication packet'
...
Bootstrap 3 modal vertical position center
...: inline-block;
vertical-align: middle;
content: " ";
height: 100%;
}
}
.modal-dialog {
display: inline-block;
text-align: left;
vertical-align: middle;
}
And adjust a little bit .fade class to make sure it appears out of the top border of window, instead of center
...
Set Colorbar Range in matplotlib
...port matplotlib.pyplot as plt
import numpy as np
cdict = {
'red' : ( (0.0, 0.25, .25), (0.02, .59, .59), (1., 1., 1.)),
'green': ( (0.0, 0.0, 0.0), (0.02, .45, .45), (1., .97, .97)),
'blue' : ( (0.0, 1.0, 1.0), (0.02, .75, .75), (1., 0.45, 0.45))
}
cm = m.colors.LinearSegmentedColormap('...
How to configure PostgreSQL to accept all incoming connections
...
Just use 0.0.0.0/0.
host all all 0.0.0.0/0 md5
Make sure the listen_addresses in postgresql.conf (or ALTER SYSTEM SET) allows incoming connections on all available IP interfaces.
listen_addres...
CSS performance relative to translateZ(0)
...ng' the GPU to think that an element is 3D by using transform: translateZ(0) to speed up animations and transitions. I was wondering if there are implications to using this transform in the following manner:
...
How to change plot background color?
...an use set_facecolor:
ax.set_facecolor('xkcd:salmon')
ax.set_facecolor((1.0, 0.47, 0.42))
As a refresher for what colors can be:
matplotlib.colors
Matplotlib recognizes the following formats to specify a color:
an RGB or RGBA tuple of float values in [0, 1] (e.g., (0.1, 0.2, 0....