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Replace a value if null or undefined in JavaScript
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Here’s the JavaScript equivalent:
var i = null;
var j = i || 10; //j is now 10
Note that the logical operator || does not return a boolean value but the first value that can be converted to true.
Additionally use an array of objects instead of one single object:
var options = {
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Numpy how to iterate over columns of array?
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– Ibrahim Muhammad
Sep 23 '13 at 17:08
49
For those wondering, array.T isn't costly, as it just c...
What is the Ruby (spaceship) operator?
...ther language that supports it. Basically instead of returning 1 (true) or 0 (false) depending on whether the arguments are equal or unequal, the spaceship operator will return 1, 0, or −1 depending on the value of the left argument relative to the right argument.
a <=> b :=
if a < b t...
How do I calculate a point on a circle’s circumference?
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600
The parametric equation for a circle is
x = cx + r * cos(a)
y = cy + r * sin(a)
Where r is t...
Adding a y-axis label to secondary y-axis in matplotlib
...directly
import numpy as np
import matplotlib.pyplot as plt
x = np.arange(0, 10, 0.1)
y1 = 0.05 * x**2
y2 = -1 *y1
fig, ax1 = plt.subplots()
ax2 = ax1.twinx()
ax1.plot(x, y1, 'g-')
ax2.plot(x, y2, 'b-')
ax1.set_xlabel('X data')
ax1.set_ylabel('Y1 data', color='g')
ax2.set_ylabel('Y2 data', color...
How to sleep for five seconds in a batch file/cmd [duplicate]
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30 Answers
30
Active
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Linux/Unix command to determine if process is running?
...ps cax | grep command
The output on Gentoo Linux:
14484 ? S 0:00 apache2
14667 ? S 0:00 apache2
19620 ? Sl 0:00 apache2
21132 ? Ss 0:04 apache2
The output on OS X:
42582 ?? Z 0:00.00 (smbclient)
46529 ?? Z 0:00.00 (smbclient)
46539...
Append integer to beginning of list in Python [duplicate]
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10 Answers
10
Active
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For loop example in MySQL
...ot null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedure load_foo_test_data()
begin
declare v_max int unsigned default 1000;
declare v_counter int unsigned default 0;
truncate table f...
How to trim leading and trailing white spaces of a string?
... Denys SéguretDenys Séguret
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