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List vs List
...d your scenario there. However, you can help the compiler by giving him a hint:
List<Car> cars;
List<? extends Automobile> automobiles = cars; // no error
Contravariance
The reverse of co-variance is contravariance. Where in covariance the parameter types must have a subtype relati...
Reuse Cucumber steps
...thing", "fill something". The natural way would be reuse steps, instead of convert each step into a call to a function. IMO, calling steps inside steps should just be improved.
– dgmora
Jun 27 '13 at 16:28
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How can you find the height of text on an HTML canvas?
...ind out how tall it is. I know it's based on the font, but I don't know to convert a font string to a text height.
23 Answe...
Python group by
...ultdict(list)
>>> for v, k in input: res[k].append(v)
...
Then, convert that dictionary into the expected format.
>>> [{'type':k, 'items':v} for k,v in res.items()]
[{'items': ['9085267', '11788544'], 'type': 'NOT'}, {'items': ['5238761', '5349618', '962142', '7795297', '7341464...
When to use Hadoop, HBase, Hive and Pig?
...n to my answer. No self promotion intended)
Both Hive and Pig queries get converted into MapReduce jobs under the hood.
HTH
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What can you use Python generator functions for?
...ted to collect all results in a list, the generator approach is trivial to convert to the big-list approach:
big_list = list(the_generator)
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What is the relationship between Looper, Handler and MessageQueue in Android?
...ead (a subclass of Thread).
A Handler is a utility class that facilitates interacting with a Looper—mainly by posting messages and Runnable objects to the thread's MessageQueue. When a Handler is created, it is bound to a specific Looper (and associated thread and message queue).
In typical usag...
How to write header row with csv.DictWriter?
...g (i.e. do-nothing) dict out of your fieldnames so that csv.DictWriter can convert it back to a list and pass it to a csv.writer instance.
(2) The documentation mentions "the underlying writer instance" ... so just use it (example at the end).
dw.writer.writerow(dw.fieldnames)
(3) Avoid the csv...
Handle file download from ajax post
...ersion using jQuery.ajax. It might mangle binary data when the response is converted to a string of some charset.
$.ajax({
type: "POST",
url: url,
data: params,
success: function(response, status, xhr) {
// check for a filename
var filename = "";
var disposit...
Use RSA private key to generate public key?
...revious command. Try running the following commands and compare output:
# Convert the key from PEM to DER (binary) format
openssl rsa -in private.pem -outform der -out private.der
# Print private.der private key contents as binary stream
xxd -p private.der
# Now compare the output of the above co...