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How can I count the occurrences of a list item?
...ions import Counter;n=1000;l=[random.choice(string.ascii_letters) for x in range(n)]'
)
t2=timeit.Timer('[[x,l.count(x)] for x in set(l)]',
'import random;import string;n=1000;l=[random.choice(string.ascii_letters) for x in range(n)]'
)
print("Counte...
python generator “send” function purpose?
...
This function is to write coroutines
def coroutine():
for i in range(1, 10):
print("From generator {}".format((yield i)))
c = coroutine()
c.send(None)
try:
while True:
print("From user {}".format(c.send(1)))
except StopIteration: pass
prints
From generator 1
From u...
Is there a Python function to determine which quarter of the year a date is in?
... 1 to 12, it's easy to check for yourself what formula is right:
for m in range(1, 13):
print m//4 + 1,
print
gives 1 1 1 2 2 2 2 3 3 3 3 4 -- two four-month quarters and a single-month one (eep).
for m in range(1, 13):
print (m-1)//3 + 1,
print
gives 1 1 1 2 2 2 3 3 3 4 4 4 -- now doesn't...
How do I get the row count of a pandas DataFrame?
...fplot
perfplot.save(
"out.png",
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda data: data.shape[0],
lambda data: data[0].count(),
lambda data: len(data.index),
],
labels=["data.shape[...
Switch on ranges of integers in JavaScript [duplicate]
...ne");
break;
}
It is not necessary to check the lower end of the range because the break statements will cause execution to skip remaining cases, so by the time execution gets to checking e.g. (x < 9) we know the value must be 5 or greater.
Of course the output is only correct if the c...
Reading an Excel file in PHP [closed]
...
PHPExcel has always been able to read and to write a range of spreadsheet formats. Quoting from the first non-heading line of the home page: "Project providing a set of classes for the PHP programming language, which allow you to write to and read from different file formats, l...
Sequence-zip function for c++11?
With the new range-based for loop we can write code like
13 Answers
13
...
How could I use requests in asyncio?
...
'http://example.org/'
)
for i in range(20)
]
for response in await asyncio.gather(*futures):
pass
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
...
How do I plot in real-time in a while loop using matplotlib?
...y as np
import matplotlib.pyplot as plt
plt.axis([0, 10, 0, 1])
for i in range(10):
y = np.random.random()
plt.scatter(i, y)
plt.pause(0.05)
plt.show()
Note some of the changes:
Call plt.pause(0.05) to both draw the new data and it runs the GUI's event loop (allowing for mouse in...
Index all *except* one item in python
...st comp. For example, to make b a copy of a without the 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays...