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How to create a temporary directory?
I use to create a tempfile , delete it and recreate it as a directory:
4 Answers
4
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Can a foreign key be NULL and/or duplicate?
...als. Suppose further that each proposal only has one sales person assigned and one client. So your proposal table would have two foreign keys, one with the client ID and one with the sales rep ID. However, at the time the record is created, a sales rep is not always assigned (because no one is fre...
Setting the selected value on a Django forms.ChoiceField
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the tuples represent (value, label) pairs for the options and you want to specify the initial value - so the '3' refers to the first item.
– Tom
Oct 29 '17 at 10:19
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How to reset a single table in rails?
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In case anyone tried this and got an error, I did ActiveRecord::Base.connection.execute("DELETE from 'yourtablename'") and it worked because it would give me an error that said sqlite_sequence where name = 'yourtablename' is not a valid table name or ...
Coding Practices which enable the compiler/optimizer to make a faster program
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Write to local variables and not output arguments! This can be a huge help for getting around aliasing slowdowns. For example, if your code looks like
void DoSomething(const Foo& foo1, const Foo* foo2, int numFoo, Foo& barOut)
{
for (int...
doGet and doPost in Servlets
...information to a Servlet. In the Servlet, I am using the methods doGet() and doPost() :
5 Answers
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Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
Is there a rule-of-thumb for how to best divide data into training and validation sets? Is an even 50/50 split advisable? Or are there clear advantages of having more training data relative to validation data (or vice versa)? Or is this choice pretty much application dependent?
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Center a position:fixed element
...a position: fixed; popup box centered to the screen with a dynamic width and height. I used margin: 5% auto; for this. Without position: fixed; it centers fine horizontally, but not vertically. After adding position: fixed; , it's even not centering horizontally.
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Inspect element that only appear when other element is mouse overed/entered
...g over the button
Press F8 to freeze the page
Switch to the Elements panel and use the magnifying glass icon in the top left to select the tooltip
If the tooltip shows up because of CSS, here's what you can do in that case:
Step-by-step:
Open the DevTools
Select the triggering element in the d...
How do I seed a random class to avoid getting duplicate random values [duplicate]
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You should not create a new Random instance in a loop. Try something like:
var rnd = new Random();
for(int i = 0; i < 100; ++i)
Console.WriteLine(rnd.Next(1, 100));
The sequence of random numbers generated by a single Random instance is suppose...