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How can I obtain the element-wise logical NOT of a pandas Series?
...~s:
In [7]: s = pd.Series([True, True, False, True])
In [8]: ~s
Out[8]:
0 False
1 False
2 True
3 False
dtype: bool
Using Python2.7, NumPy 1.8.0, Pandas 0.13.1:
In [119]: s = pd.Series([True, True, False, True]*10000)
In [10]: %timeit np.invert(s)
10000 loops, best of 3: 91.8 µs...
How to check if hex color is “too black”?
...Int(c, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff; // extract blue
var luma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709
if (luma < 40) {
...
What's the (hidden) cost of Scala's lazy val?
...uivalent to the following Java code:
class LazyTest {
public int bitmap$0;
private String msg;
public String msg() {
if ((bitmap$0 & 1) == 0) {
synchronized (this) {
if ((bitmap$0 & 1) == 0) {
synchronized (this) {
msg = "La...
User recognition without cookies or local storage
...
+350
Introduction
If I understand you correctly, you need to identify a user for whom you don't have a Unique Identifier, so you want to f...
Setting different color for each series in scatter plot on matplotlib
...
280
I don't know what you mean by 'manually'. You can choose a colourmap and make a colour array ea...
How can I check if an ip is in a network in Python?
Given an ip address (say 192.168.0.1), how do I check if it's in a network (say 192.168.0.0/24) in Python?
27 Answers
...
How to decide font color in white or black depending on background color?
...overall intensity of the color and choose the corresponding text.
if (red*0.299 + green*0.587 + blue*0.114) > 186 use #000000 else use #ffffff
The threshold of 186 is based on theory, but can be adjusted to taste. Based on the comments below a threshold of 150 may work better for you.
Edit: T...
Outline effect to text
...stroked text:
.strokeme {
color: white;
text-shadow: -1px -1px 0 #000, 1px -1px 0 #000, -1px 1px 0 #000, 1px 1px 0 #000;
}
<div class="strokeme">
This text should have a stroke in some browsers
</div>
I have made a demo for you here
And a hovered example is avai...
pyplot scatter plot marker size
...xamples and the output they produce.
# doubling the width of markers
x = [0,2,4,6,8,10]
y = [0]*len(x)
s = [20*4**n for n in range(len(x))]
plt.scatter(x,y,s=s)
plt.show()
gives
Notice how the size increases very quickly. If instead we have
# doubling the area of markers
x = [0,2,4,6,8,10]
y ...
Why am I getting a “401 Unauthorized” error in Maven?
Why am I getting a "401 Unauthorized" error in Maven?
21 Answers
21
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