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What does -1 mean in numpy reshape?

... (-1,3) but not (-1, -1)). It simply means that it is an unknown dimension and we want numpy to figure it out. And numpy will figure this by looking at the 'length of the array and remaining dimensions' and making sure it satisfies the above mentioned criteria Now see the example. z = np.array([[...
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Factors in R: more than an annoyance?

... data types in R is factors. In my experience factors are basically a pain and I never use them. I always convert to characters. I feel oddly like I'm missing something. ...
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Why use the params keyword?

...ly doing to make the best choice. – Allen Clark Copeland Jr Nov 28 '15 at 22:15 2 ...
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Seedable JavaScript random number generator

The JavaScript Math.random() function returns a random value between 0 and 1, automatically seeded based on the current time (similar to Java I believe). However, I don't think there's any way to set you own seed for it. ...
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MySQL ON vs USING?

In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...
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Append an object to a list in R in amortized constant time, O(1)?

...oldlist, list(someobj)) In general, R types can make it hard to have one and just one idiom for all types and uses. share | improve this answer | follow | ...
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Difference between MEAN.js and MEAN.io

... noticed that there are two different stacks with either their own website and installation methods: mean.js and mean.io. So I came up asking myself this question: "Which one do I use?". ...
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How can I troubleshoot my Perl CGI script?

I have a Perl script that isn't working and I don't know how to start narrowing down the problem. What can I do? 8 Answers ...
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How to add a progress bar to a shell script?

When scripting in bash or any other shell in *NIX, while running a command that will take more than a few seconds, a progress bar is needed. ...
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Which equals operator (== vs ===) should be used in JavaScript comparisons?

I'm using JSLint to go through JavaScript, and it's returning many suggestions to replace == (two equals signs) with === (three equals signs) when doing things like comparing idSele_UNVEHtype.value.length == 0 inside of an if statement. ...