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COUNT DISTINCT with CONDITIONS
... only positive values. Zeros or negative values would be evaluated as null and won't be included in count.
One thing to note here is that this can be done by reading the table once. When it seems that you have to read the same table twice or more, it can actually be done by reading once, in most of...
How to create a hex dump of file containing only the hex characters without spaces in bash?
...te an unmodified hex dump of a binary file in Linux using bash? The od and hexdump commands both insert spaces in the dump and this is not ideal.
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Converting bool to text in C++
...any way to convert a boolean value to a string such that 1 turns to "true" and 0 turns to "false"? I could just use an if statement, but it would be nice to know if there is a way to do that with the language or standard libraries. Plus, I'm a pedant. :)
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Compare version numbers without using split function
... @dev_Boston only one exception...just do with these values v1=1.0001 and v2=1.1 .it gives me equal.
– Sankar M
Sep 27 '11 at 11:31
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How can I install pip on Windows?
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Python 2.7.9+ and 3.4+
Good news! Python 3.4 (released March 2014) and Python 2.7.9 (released December 2014) ship with Pip. This is the best feature of any Python release. It makes the community's wealth of libraries accessible to everyon...
What is the difference between class and instance methods?
What's the difference between a class method and an instance method?
18 Answers
18
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How to find all positions of the maximum value in a list?
... 0 for this is 2n, the list is iterated through 2x, once to determine max, and another time to find the positions of the max. A for loop that tracks the current max and its position might be more efficient for really long lists.
– radtek
Jan 8 '15 at 18:42
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How to check if a string array contains one string in JavaScript? [duplicate]
I have a string array and one string. I'd like to test this string against the array values and apply a condition the result - if the array contains the string do "A", else do "B".
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How can I check if a checkbox is checked?
I am building a mobile web app with jQuery Mobile and I want to check if a checkbox is checked. Here is my code.
14 Answers...
dplyr: “Error in n(): function should not be called directly”
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I presume you have dplyr and plyr loaded in the same session. dplyr is not plyr. ddply is not a function in the dplyr package.
Both dplyr and plyr have the functions summarise/summarize.
Look at the results of conflicts() to see masked objects.
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