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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...pply is generally not much faster than iterating over a Python list. Let's test the performance of a for-loop to do the same thing as above
%%timeit
A1, A2 = [], []
for val in df['a']:
A1.append(val**2)
A2.append(val**3)
df['A1'] = A1
df['A2'] = A2
298 ms ± 7.14 ms per loop (mean ± std....
What is the difference between String.slice and String.substring?
...ge values are truncated to the length of the string:
alert ( "testme" .substring (-2)); // "testme", -2 becomes 0
Furthermore, if start > end, the arguments are interchanged, i.e. plot line returns between the start and end:
alert ( "testme" .substring (4, -1)); // "test"
// -1 Bec...
How can I get all constants of a type by reflection?
...not sure about the assertions with regards to IsLiteral and IsInitOnly. On testing it would seem that for static readonly properties IsLiteral is always false - so IsLiteral is the only flag you need to check to find constants and you can ignore IsInitOnly. I tried with different field types (e.g. S...
Bootstrap combining rows (rowspan)
I am testing Twitter Bootstrap and got stuck with
basic scaffolding with rows. I revisited their documentation number of times and I can see nesting columns where you can basically nest columns within a column but I cannot locate
the capability of combining rows into one and have it aligned with ...
Passing command line arguments from Maven as properties in pom.xml
...le, where they can then be accessed from your Java code.
In my case it is test code that needs to access this properties file, so in the pom the properties file is written to maven's testOutputDirectory:
<configuration>
<outputFile>${project.build.testOutputDirectory}/my.properties...
Create code first, many to many, with additional fields in association table
...
@Esteban, the code you provided is right, thanks, but incomplete, I've tested it. There are missing properties in "UserEmail" class:
public UserTest UserTest { get; set; }
public EmailTest EmailTest { get; set; }
I post the code I've tested if someone is interested.
Regards
using Sys...
Hook up Raspberry Pi via Ethernet to laptop without router? [closed]
...ase for most recent hardware, including for example the 2012 Lenovo T430 I tested with, which has an "Intel® 82579LM Gigabit Network Connection" which documents support for Auto MDI-X.
Now you can also:
access the Internet from the PI through your Ubuntu's Wifi connection
open a VNC to get rid o...
How to free memory in Java?
... @Pablo Santa Cruz What do you mean it does not free memory? I just tested it out on my program that seemed to have a leak and the ram usage seemed to stabilize? And Daniel just said it only suggests it then how come the percentage of ram used always stabilized each time I called the method. ...
How to deal with page breaks when printing a large HTML table
...p-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Test</title>
<style type="text/css">
table { page-break-inside:auto }
tr { page-break-inside:avoid; page-break-after:auto }
thead { display:table-header-group }
tfoot { display:table-footer-grou...
Remove empty elements from an array in Javascript
...
this.splice(i, 1);
i--;
}
}
return this;
};
test = new Array("", "One", "Two", "", "Three", "", "Four").clean("");
test2 = [1, 2,, 3,, 3,,,,,, 4,, 4,, 5,, 6,,,,];
test2.clean(undefined);
Or you can simply push the existing elements into other array:
// Will remove a...