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What is the difference between join and merge in Pandas?
...ys use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
ba...
How can I view the source code for a function?
...ot me close to what I wanted. What I actually wanted, in RStudio, was View(foo); where foo was a function from an already loaded package.
– Sigfried
Feb 28 '19 at 11:35
1
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How can I check if a program exists from a Bash script?
...ms have a which that doesn't even set an exit status, meaning the if which foo won't even work there and will always report that foo exists, even if it doesn't (note that some POSIX shells appear to do this for hash too).
Many operating systems make which do custom and evil stuff like change the out...
How do you run a single test/spec file in RSpec?
...or example, if you had a spec like:
1:
2: it "should be awesome" do
3: foo = 3
4: foo.should eq(3)
5: end
6:
Let's say it's saved in spec/models/foo_spec.rb. Then you would run:
rspec spec/models/foo_spec.rb:2
and it would just run that one spec. In fact, that number could be anything f...
How do I tell if a regular file does not exist in Bash?
...amation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
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How do I convert a dictionary to a JSON String in C#?
...tring[] args)
{
Dictionary<int, List<int>> foo = new Dictionary<int, List<int>>();
foo.Add(1, new List<int>( new int[] { 1, 2, 3, 4 }));
foo.Add(2, new List<int>(new int[] { 2, 3, 4, 1 }));
foo.Add(3, new Li...
How do I create a namespace package in Python?
...means there are now three types of object that can be created by an import foo:
A module represented by a foo.py file
A regular package, represented by a directory foo containing an __init__.py file
A namespace package, represented by one or more directories foo without any __init__.py files
Pac...
How do I check if an integer is even or odd? [closed]
...nness(object o)
{
if (o == null)
return Evenness.Unknown;
string foo = o.ToString();
if (String.IsNullOrEmpty(foo))
return Evenness.Unknown;
char bar = foo[foo.Length - 1];
switch (bar)
{
case '0':
case '2':
case '4':
case '6':
case '8':
retur...
ld cannot find an existing library
...
The foo.so.1 is a symlink to foo.so.1.0.0 too. This way, you can have several versions of a library in your system, and if an application needs a specific one, it can link to it, while in general, the newest one is chosen by sym...
Parsing JSON using Json.net
... public int x { get; set; }
public int y { get; set; }
}
public class Foo
{
public Foo() { objects = new List<SubObject>(); }
public string displayFieldName { get; set; }
public NameTypePair fieldAliases { get; set; }
public PositionType positionType { get; set; }
publ...