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Difference between map, applymap and apply methods in Pandas
Can you tell me when to use these vectorization methods with basic examples?
10 Answers
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Cast to int vs floor
...) = -5
(int)(-4.5) = -4
This being said, there is also a difference in execution time. On my system, I've timed that casting is at least 3 times faster than floor.
I have code that needs the floor operation of a limited range of values, including negative numbers. And it needs to be very effici...
Get number of digits with JavaScript
...post suggests, I would like to know how many digits var number has. For example: If number = 15; my function should return 2 . Currently, it looks like this:
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How to store date/time and timestamps in UTC time zone with JPA and Hibernate
...ored or has no effect when used with PostgreSQL
– Alex R
Apr 29 '19 at 0:26
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show 4 more comments
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pyplot scatter plot marker size
...it increases it by a factor of 4). To see this consider the following two examples 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 quickl...
Programmatically scroll a UIScrollView
...lowing statements in Objective-C
[scrollView setContentOffset:CGPointMake(x, y) animated:YES];
or Swift
scrollView.setContentOffset(CGPoint(x: x, y: y), animated: true)
See the guide "Scrolling the Scroll View Content" from Apple as well.
To do slideshows with UIScrollView, you arrange all im...
How to check if a variable is an integer in JavaScript?
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Check if a value is within a range of numbers
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You're asking a question about numeric comparisons, so regular expressions really have nothing to do with the issue. You don't need "multiple if" statements to do it, either:
if (x >= 0.001 && x <= 0.009) {
// something
}
You could write yourself a "between()" function...
Getting indices of True values in a boolean list
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Use enumerate, list.index returns the index of first match found.
>>> t = [False, False, False, False, True, True, False, True, False, False, False, False, False, False, False, False]
>>> [i for i, x in enumerate(t) if x]
[4, 5, 7...
How do I tell Matplotlib to create a second (new) plot, then later plot on the old one?
...lotlib. In your case:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(5)
y = np.exp(x)
fig1, ax1 = plt.subplots()
ax1.plot(x, y)
ax1.set_title("Axis 1 title")
ax1.set_xlabel("X-label for axis 1")
z = np.sin(x)
fig2, (ax2, ax3) = plt.subplots(nrows=2, ncols=1) # two axes on figure...