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S3 Error: The difference between the request time and the current time is too large
...ifference between the request time and the current time is too large when call method amazons3.ListObjects
18 Answers
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
...td. dev. of 7 runs, 10 loops each)
60x faster than zip
In general, avoid using apply
Apply is generally not much faster than iterating over a Python list. Let's test the performance of a for-loop to do the same thing as above
%%timeit
A1, A2 = [], []
for val in df['a']:
A1.append(val**2)
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How can I convert my device token (NSData) into an NSString?
...later version of iOS will not change the implementation and result of this call.
– madewulf
Nov 14 '12 at 14:00
17
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Regex lookahead for 'not followed by' in grep
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If you don't have (a sufficiently recent version of) GNU grep, then consider getting ack.
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How to compare variables to undefined, if I don’t know whether they exist? [duplicate]
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That was not the question though. Just because you call a variable obj it may still be anything imho.
– andig
Jun 21 '15 at 9:03
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C compile error: “Variable-sized object may not be initialized”
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I am assuming that you are using a C99 compiler (with support for dynamically sized arrays). The problem in your code is that at the time when the compilers sees your variable declaration it cannot know how many elements there are in the array (I am also assuming here, from the compiler error tha...
Finding Number of Cores in Java
...s number of physical cores .
private int getNumberOfCPUCores() {
OSValidator osValidator = new OSValidator();
String command = "";
if(osValidator.isMac()){
command = "sysctl -n machdep.cpu.core_count";
}else if(osValidator.isUnix()){
command = "lscpu";
}else if(o...
How can I obtain the element-wise logical NOT of a pandas Series?
...ctually tested the tilde as it was mentioned in the documentation, but it didn't perform the same as np.invert :S
– root
Apr 14 '13 at 13:11
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How do I sort a list of dictionaries by a value of the dictionary?
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sorted using timsort which is stable, you can call sorted several times to have a sort on several criteria
– njzk2
May 29 '13 at 13:41
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Is there any performance reason to declare method parameters final in Java?
... enough to need this level of engineering, make them smaller - methods you call can't change your parameters.
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