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Difference between DateTime and Time in Ruby
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Newer versions of Ruby (2.0+) do not really have significant differences between the two classes. Some libraries will use one or the other for historical reasons, but new code does not necessarily need to be concerned. Picking one for consistency is p...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
...where)
As a worked example:
import pandas as pd
>>> df
country
0 US
1 UK
2 Germany
3 China
>>> countries_to_keep
['UK', 'China']
>>> df.country.isin(countries_to_keep)
0 False
1 True
2 False
3 True
Name: country, dtype: bool
>>>...
Matplotlib discrete colorbar
...rm as normalizer for your scatter. The quirky bit (in my method) is making 0 showup as grey.
For images i often use the cmap.set_bad() and convert my data to a numpy masked array. That would be much easier to make 0 grey, but i couldnt get this to work with the scatter or the custom cmap.
As an ...
Convert column classes in data.table
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105
For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘d...
How to get a pixel's x,y coordinate color from an image?
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202
Building on Jeff's answer, your first step would be to create a canvas representation of your P...
Could not load file or assembly 'System.Net.Http.Formatting' or one of its dependencies. The system
... dll's I need for my MVC program.
EDIT >>>
For Visual Studio 2013 and above, step 2) should read:
Open Visual Studio and go to Tools > Options > NuGet Package Manager and on the right hand side there is a "Clear Package Cache button". Click this button and make sure that the che...
How do you create a yes/no boolean field in SQL server?
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The equivalent is a BIT field.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions).
When accessing the database through ASP.NET it will expose the field as a b...
How many double numbers are there between 0.0 and 1.0?
...e), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's the number of distinct doubles between 0.5 included and 1.0 excluded, and exactly that many also lie between 1.0 included and 2.0 excluded, and so forth.
Counting the doubles bet...
How to check if an int is a null
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An int is not null, it may be 0 if not initialized.
If you want an integer to be able to be null, you need to use Integer instead of int.
Integer id;
String name;
public Integer getId() { return id; }
Besides the statement if(person.equals(null)) can...
Generate random integers between 0 and 9
How can I generate random integers between 0 and 9 (inclusive) in Python?
19 Answers
1...