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How to make good reproducible pandas examples
... this is similar to r's expand.grid(), see note 2 below
'd':np.repeat( range(3), 2 ),
'e':np.tile( range(2), 3 ),
# a date range and set of random dates
'f':pd.date_range('1/1/2011', periods=6, freq='D'),
'g':np.random.choice( pd.date_range('1/1/2011', periods=365,
...
Is the size of C “int” 2 bytes or 4 bytes?
...hat can be confusing at first, but the C standard only specifies a minimum range for integer types that is guaranteed to be supported. int is guaranteed to be able to hold -32767 to 32767, which requires 16 bits. In that case, int, is 2 bytes. However, implementations are free to go beyond that mini...
MySQL vs MongoDB 1000 reads
...index, we can assume that the values for the root row are in the index
20+ range lookups (hopefully on an index) for the entity's pk value
These probably aren't clustered indexes, so the same 20+ data lookups once we figure out what the appropriate child rows are.
So the total for mysql, even assu...
Can't pickle when using multiprocessing Pool.map()
... go(self):
... pool = pp.ProcessPool(4)
... print pool.map(self.f, range(10))
...
>>> sc = someClass()
>>> sc.go()
[0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
>>>
Get the code here:
https://github.com/uqfoundation/pathos
...
Change values while iterating
...o, the abbreviation you want is not possible.
The reason for this is that range copies the values from the slice you're iterating over.
The specification about range says:
Range expression 1st value 2nd value (if 2nd variable is present)
array or slice a [n...
How to suppress scientific notation when printing float values?
... += str(coef).replace('.', '')
return_val += ''.join(['0' for _ in range(0, abs(exp - len(str(coef).split('.')[1])))])
elif int(exp) < 0:
return_val += '0.'
return_val += ''.join(['0' for _ in range(0, abs(exp) - 1)])
return_val += str(coef).replace('.', '')
...
Is there a way to iterate over a slice in reverse in Go?
...
No there is no convenient operator for this to add to the range one in place. You'll have to do a normal for loop counting down:
s := []int{5, 4, 3, 2, 1}
for i := len(s)-1; i >= 0; i-- {
fmt.Println(s[i])
}
...
Why dict.get(key) instead of dict[key]?
... includes looking up all the valid keys only)
def getway(d):
for i in range(100):
s = d.get(i)
def lookup(d):
for i in range(100):
s = d[i]
Now timing these two functions using timeit
>>> import timeit
>>> print(timeit.timeit("getway({i:i for i in range...
Creating an empty Pandas DataFrame, then filling it?
...
Here's a couple of suggestions:
Use date_range for the index:
import datetime
import pandas as pd
import numpy as np
todays_date = datetime.datetime.now().date()
index = pd.date_range(todays_date-datetime.timedelta(10), periods=10, freq='D')
columns = ['A','B', '...
Is there a replacement for unistd.h for Windows (Visual C)?
...a
* common MinGW API in libmingwex.a, providing for suspension periods
* ranging from mean values of ~7.5 milliseconds, (see the comments in
* <time.h>), extending up to a maximum of ~136 years.
*
* Note that, whereas POSIX supports early wake-up of any suspended
* process/thread, in res...