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How do I make class methods / properties in Swift?
... than an NSObject class in Objective-C and that was already pretty easy to setup.
– Supertecnoboff
Jan 1 '16 at 11:40
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How to secure an ASP.NET Web API [closed]
...umerable<string> values;
if (!request.Headers.TryGetValues("Set-Cookie", out values))
{
return new NameValueCollection();
}
var header = values.FirstOrDefault();
return this.CollectCookiesFromHeaderString(header);
}
/// <summar...
How do I modify fields inside the new PostgreSQL JSON datatype?
...onb '["a",1]' || jsonb '["b",2]' -- will yield jsonb '["a",1,"b",2]'
So, setting a simple key can be done using:
SELECT jsonb '{"a":1}' || jsonb_build_object('<key>', '<value>')
Where <key> should be string, and <value> can be whatever type to_jsonb() accepts.
For setting ...
How to store standard error in a variable
...pipe is sent to stdout for display or to be piped into another command.
It sets up a couple of extra file descriptors to manage the redirections needed in order to do this.
#!/bin/bash
exec 3>&1 4>&2 #set up extra file descriptors
error=$( { ./useless.sh | sed 's/Output/Useless/' 2&g...
Assign pandas dataframe column dtypes
I want to set the dtype s of multiple columns in pd.Dataframe (I have a file that I've had to manually parse into a list of lists, as the file was not amenable for pd.read_csv )
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Dynamically select data frame columns using $ and a character value
...m to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
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How do you allow spaces to be entered using scanf?
Using the following code:
11 Answers
11
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How to activate an Anaconda environment
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If this happens you would need to set the PATH for your environment (so that it gets the right Python from the environment and Scripts\ on Windows).
Imagine you have created an environment called py33 by using:
conda create -n py33 python=3.3 anaconda
Her...
data.table vs dplyr: can one do something well the other can't or does poorly?
...over these remaining aspects as well:
Grouping operations involving a subset of rows - i.e., DT[x > val, sum(y), by = z] type operations.
Benchmark other operations such as update and joins.
Also benchmark memory footprint for each operation in addition to runtime.
2. Memory usage
Operation...
Check if a path represents a file or a folder
I need a valid method to check if a String represents a path for file or a directory. What are valid directory names in Android? As it comes out, folder names can contain '.' chars, so how does system understand whether there's a file or a folder?
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