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How do I create a dynamic key to be added to a JavaScript object variable [duplicate]
...
Square brackets:
jsObj['key' + i] = 'example' + 1;
In JavaScript, all arrays are objects, but not all objects are arrays. The primary difference (and one that's pretty hard to mimic with straight JavaScript and plain objects) is that array instances maintain the length property so that it r...
How to get the first element of an array?
...code. It simply shows undefined, since that's the value of a[0], which actually is the first item in the array. If you want it to show foo you should skip all undefined values but it wouldn't be the first item in the array.
– Michiel van der Blonk
Sep 6 '16 at ...
How do I make a simple makefile for gcc on Linux?
...ple as possible by omitting variables like $(CC) and $(CFLAGS) that are usually seen in makefiles. If you're interested in figuring that out, I hope I've given you a good start on that.
Here's the Makefile I like to use for C source. Feel free to use it:
TARGET = prog
LIBS = -lm
CC = gcc
CFLAGS ...
Java HashMap performance optimization / alternative
...={99,100}) will hash to the same value as (a[]={3,1,2}, b[]={100,99}). Actually all keys k1 and k2 where sum(k1.a)==sum(k2.a) and sum(k1.b)=sum(k2.b) will result in collisions. I suggest assigning a weight to each position of the array:
hash = hash * 5381 + (c0*a[0] + c1*a[1]);
hash = hash * 5381 +...
Multiple file extensions in OpenFileDialog
...te groups so JPG are *.jpg and *.jpeg, TIFF are *.tif and *.tiff and also 'All graphic types'? How can I do that?
3 Answers...
How can I make an entire HTML form “readonly”?
...the submission form again with a confirmation message. On this second form all fields must be static.
12 Answers
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How to print a dictionary's key?
...no "the key". You have the keys() method, which gives you a python list of all the keys, and you have the iteritems() method, which returns key-value pairs, so
for key, value in mydic.iteritems() :
print key, value
Python 3 version:
for key, value in mydic.items() :
print (key, value)
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Detect and exclude outliers in Pandas data frame
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If you have multiple columns in your dataframe and would like to remove all rows that have outliers in at least one column, the following expression would do that in one shot.
df = pd.DataFrame(np.random.randn(100, 3))
from scipy import stats
df[(np.abs(stats.zscore(df)) < 3).all(axis=1)]
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Deleting queues in RabbitMQ
...rgin state.
Removes the node from any cluster it belongs to, removes all data from
the management database, such as configured users and vhosts, and
deletes all persistent messages.
So, be careful using it.
share...
Generate array of all letters and digits
...ontent-policy\"\u003e(content policy)\u003c/a\u003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
...