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How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
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Remove rows with all or some NAs (missing values) in data.frame
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1080
Also check complete.cases :
> final[complete.cases(final), ]
gene hsap mmul m...
How do I measure execution time of a command on the Windows command line?
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30 Answers
30
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Where can I find a NuGet package for upgrading to System.Web.Http v5.0.0.0?
Just upgraded an ASP.NET MVC4 project to use Unity.WebApi version 5.0.0.0 and it requires System.Web.Http v 5.0.0.0 as per the following error:
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Boolean Field in Oracle
...as JDBC, OCCI, and other programming environments,
it's better to select 0 for false and 1 for true so it can work
correctly with the getBoolean and setBoolean functions.
Basically they advocate method number 2, for efficiency's sake, using
values of 0/1 (because of interoperability with JD...
Filter rows which contain a certain string
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mpg cyl disp hp drat wt qsec vs am gear carb type
1 21.0 6 160.0 110 3.90 2.620 16.46 0 1 4 4 Mazda RX4
2 21.0 6 160.0 110 3.90 2.875 17.02 0 1 4 4 Mazda RX4 Wag
3 33.9 4 71.1 65 4.22 1.835 19.90 1 1 4 1 Toyota Corolla
4 21.5 4 120.1 97 3....
How do you add swap to an EC2 instance?
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10 Answers
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Pandas percentage of total with groupby
...swer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'office_id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12...
How to add a new row to an empty numpy array
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The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...