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Read specific columns from a csv file with csv module?
...is spectacular for dealing with csv files, and the following code would be all you need to read a csv and save an entire column into a variable:
import pandas as pd
df = pd.read_csv(csv_file)
saved_column = df.column_name #you can also use df['column_name']
so if you wanted to save all of the inf...
What is a serialVersionUID and why should I use it?
...ization runtime associates with each serializable class a version number, called a serialVersionUID, which is used during deserialization to verify that the sender and receiver of a serialized object have loaded classes for that object that are compatible with respect to serialization. If the receiv...
Is file append atomic in UNIX?
...ger (linux seems to have it set to 4096).
This assume that you're talking all fully POSIX-compliant components. For instance, this isn't true on NFS.
But assuming you write to a log file you opened in 'O_APPEND' mode and keep your lines (including newline) under 'PIPE_BUF' bytes long, you should ...
What are the best practices for using Assembly Attributes?
...
We're using a global file called GlobalAssemblyInfo.cs and a local one called AssemblyInfo.cs. The global file contains the following attributes:
[assembly: AssemblyProduct("Your Product Name")]
[assembly: AssemblyCompany("Your Company")]
[assembl...
How to cherry-pick multiple commits
... and rebase second branch onto first. But is there any way to cherry-pick all c - f in one command?
12 Answers
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Why does my application spend 24% of its life doing a null check?
...t store a copy of the bytes in RAM. An important one is the L1 cache, typically 16 kilobytes for data and 16 kilobytes for instructions. Small, allowing it to be close to the execution engine. Reading bytes from the L1 cache typically takes 2 or 3 CPU cycles. Next up is the L2 cache, bigger and slow...
change type of input field with jQuery
... or part of their security model, but jQuery isn't specific):
// We can't allow the type property to be changed (since it causes problems in IE)
if ( name == "type" && jQuery.nodeName( elem, "input" ) && elem.parentNode )
throw "type property can't be changed";
...
Wrapping synchronous code into asynchronous call
... in ASP.NET application, that consumes quite a lot of time to complete. A call to this method might occur up to 3 times during one user request, depending on the cache state and parameters that user provides. Each call takes about 1-2 seconds to complete. The method itself is synchronous call to the...
hadoop No FileSystem for scheme: file
...tem, hadoop-hdfs for DistributedFileSystem) each contain a different file called org.apache.hadoop.fs.FileSystem in their META-INFO/services directory. This file lists the canonical classnames of the filesystem implementations they want to declare (This is called a Service Provider Interface impleme...
How do I remove a MySQL database?
...e users; i.e., force MySQL to read the user's privileges again.
-- DELETE ALL RECIPE
drop schema <database_name>;
-- Same as `drop database <database_name>`
drop user <a_user_name>;
-- You may need to add a hostname e.g `drop user bob@localhost`
FLUSH PRIVILEGES;
Good luck!
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