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Clojure: reduce vs. apply
... the ultimate result returned) for associative functions which need to see all their arguments in the variable-arity case. When they are result-wise equivalent, I'd say that apply is always perfectly idiomatic, while reduce is equivalent -- and might shave off a fraction of a blink of an eye -- in a...
Backup/Restore a dockerized PostgreSQL database
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Backup your databases
docker exec -t your-db-container pg_dumpall -c -U postgres > dump_`date +%d-%m-%Y"_"%H_%M_%S`.sql
Restore your databases
cat your_dump.sql | docker exec -i your-db-container psql -U postgres
...
Reduce left and right margins in matplotlib plot
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One way to automatically do this is the bbox_inches='tight' kwarg to plt.savefig.
E.g.
import matplotlib.pyplot as plt
import numpy as np
data = np.arange(3000).reshape((100,30))
plt.imshow(data)
plt.savefig('test.png', bbox_inches='tight')
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How to open every file in a folder?
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Os
You can list all files in the current directory using os.listdir:
import os
for filename in os.listdir(os.getcwd()):
with open(os.path.join(os.cwd(), filename), 'r') as f: # open in readonly mode
# do your stuff
Glob
Or you c...
What is null in Java?
... false.
It is also the default value (for variables that have them) for all reference types:
JLS 4.12.5 Initial Values of Variables
Each class variable, instance variable, or array component is initialized with a default value when it is created:
For all reference types, the defa...
How can I open a link in a new window?
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window.open('url', 'window name', 'window settings')
jQuery:
$('a#link_id').click(function(){
window.open('url', 'window name', 'window settings');
return false;
});
You could also set the target to _blank actually.
...
Reload an iframe with jQuery
...tion() {
document.location.reload();
});
and you are good to go with all browsers.
Reload an iframe with HTML (no Java Script req.)
It have more simpler solution: which works without javaScript in (FF, Webkit)
just make an anchor inSide your iframe
<a href="#" target="_SELF">Refre...
What is difference between monolithic and micro kernel?
...ing entirely in a single address space. It is a single static binary file. All kernel services exist and execute in the kernel address space. The kernel can invoke functions directly. Examples of monolithic kernel based OSs: Unix, Linux.
In microkernels, the kernel is broken down into separate proc...
How can I check a C# variable is an empty string “” or null? [duplicate]
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@Lion Liu: Actually I think PHP has exactly as much to offer. See: php.net/manual/en/function.empty.php
– Milan
Feb 2 '16 at 20:09
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Work on a remote project with Eclipse via SSH
...y what you want.
RSE may already be included in your current Eclipse installation. To check in Eclipse Indigo go to Window > Open Perspective > Other... and choose Remote System Explorer from the Open Perspective dialog to open the RSE perspective.
To create an SSH remote project from the R...