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How to convert timestamp to datetime in MySQL?
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SELECT from_unixtime( TIMESTAMP( "2011-12-01", "22:01:23.048" ) ) doesn't work. why? using v5.6
– Janus Troelsen
Feb 4 '14 at 18:44
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When do I use fabs and when is it sufficient to use std::abs?
...t, long, long long, std::intmax_t, float, double, long double. No short or char versions (or unsigned versions) that I can see.
– user673679
Mar 2 at 17:41
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Using Chrome, how to find to which events are bound to an element
...e Event you need
From the handler property, right click over function and select 'Show function definition'
You will now see the Event binding code
Click on the 'Pretty print' button for a more readable view of the code
sh...
How do I create test and train samples from one dataframe with pandas?
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scikit learn's train_test_split is a good one.
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size=0.2)
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How to open a web server port on EC2 instance
...asn't immediately clear to me from the linked instructions, but you should select "Custom TCP". Otherwise you won't be able to change the port.
– KKOrange
Dec 12 '19 at 1:39
a...
Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
Duplicate and rename Xcode project & associated folders [closed]
...ame or any associated folders at this stage.
In Xcode, rename the project. Select your project from the navigator pane (left pane). In the Utilities pane (right pane) rename your project, Accept the changes Xcode proposes.
In Xcode, rename the schemes in "Manage Schemes", also rename any targets you...
JavaScript: how to change form action attribute value based on selection?
I'm trying to change the form action based on the selected value from a dropdown menu.
5 Answers
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iOS: How to store username/password within an app?
... 3 right-click on frameworks folder and add existing framework. In Xcode 4 select your project, then select target, go to Build Phases tab and click + under Link Binary With Files) and KeychainItemWrapper .h & .m files into your project, #import the .h file wherever you need to use keychain and ...
What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...f these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.
For more guidance on this, see:
:help :map
:help :noremap
:help recursi...