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MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...-+-----+-----+-----+
| 1 | 1 | 1 | 1 |
| 10 | 10 | 10 | 10 |
| 100 | 100 | 100 | 100 |
Here a, b and c are using TINYINT(1), TINYINT(2) and TINYINT(3) respectively. As you can see, it pads the values on the left side using the display width.
It's important to note that it does not aff...
How unique is UUID?
...r words, only after generating 1 billion UUIDs every
second for the next 100 years, the probability of creating just one
duplicate would be about 50%.
Caveat:
However, these probabilities only hold when the UUIDs are generated
using sufficient entropy. Otherwise, the probability of dupli...
how do you filter pandas dataframes by multiple columns
...one from @redreamality):
import pandas as pd
import numpy as np
length = 100_000
df = pd.DataFrame()
df['Year'] = np.random.randint(1950, 2019, size=length)
df['Gender'] = np.random.choice(['Male', 'Female'], length)
%timeit df.query('Gender=="Male" & Year=="2014" ')
%timeit df[(df['Gender']=...
How to terminate the script in JavaScript?
...eyword like this:
throw new Error();
You can easily test this:
var m = 100;
throw '';
var x = 100;
x
>>>undefined
m
>>>100
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Possible to make labels appear when hovering over a point in matplotlib?
...
cmap = plt.cm.RdYlGn
fig,ax = plt.subplots()
sc = plt.scatter(x,y,c=c, s=100, cmap=cmap, norm=norm)
annot = ax.annotate("", xy=(0,0), xytext=(20,20),textcoords="offset points",
bbox=dict(boxstyle="round", fc="w"),
arrowprops=dict(arrowstyle="->"))
annot....
Easier way to create circle div than using an image?
...(PIE.htc); /* remove if you don't care about IE8 */
}
.type1 {
width: 100px;
height: 100px;
background: yellow;
border: 3px solid red;
}
.type2 {
width: 50px;
height: 50px;
background: #ccc;
border: 3px solid #000;
}
.type3 {
width: 500px;
height: 500px;
...
MySQL: Transactions vs Locking Tables
...the same type of code in parallel. They'll be retrieve your balance (say, $100), do their transactions (take out the $20 you're paying, and the $30 they're screwing you over with), and now both code paths have two different balances: $80 and $70. Depending on which ones finishes last, you'll end up ...
Ignore mouse interaction on overlay image
...;div id="menuOption" style="border:1px solid black;position:relative;width:100px;height:40px;">
sometext goes here.
<!-- Place image inside of you menu bar link -->
<img id="imgOverlay" src="w3.png" style="z-index:4;position:absolute;top:0px;left:0px;width:100px;height:40px;" \>
<!...
How to simulate a touch event in Android?
... SystemClock.uptimeMillis();
long eventTime = SystemClock.uptimeMillis() + 100;
float x = 0.0f;
float y = 0.0f;
// List of meta states found here: developer.android.com/reference/android/view/KeyEvent.html#getMetaState()
int metaState = 0;
MotionEvent motionEvent = MotionEvent.obtain(
downTime, ...
LINQ .Any VS .Exists - What's the difference?
...to evaluate both values at almost same time)
var list1 = Generate(1000000);
var forceListEval = list1.SingleOrDefault(o => o == "0123456789012");
if (forceListEval != "sdsdf")
{
var s = string.Empty;
var start2 = DateTime.Now;
i...