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Rails find record with zero has_many records associated [duplicate]
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Bah, found it here: https://stackoverflow.com/a/5570221/417872
City.includes(:photos).where(photos: { city_id: nil })
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How to create a density plot in matplotlib?
...s = np.linspace(0,8,200)
density.covariance_factor = lambda : .25
density._compute_covariance()
plt.plot(xs,density(xs))
plt.show()
I get
which is pretty close to what you are getting from R. What have I done? gaussian_kde uses a changable function, covariance_factor to calculate its bandwidth....
Adding up BigDecimals using Streams
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I see that you have added new data, therefore the new answer will become:
List<Invoice> invoiceList = new ArrayList<>();
//populate
Function<Invoice, BigDecimal> totalMapper = invoice -> invoice.getUnit_price().multiply(invoice.getQuantity());
BigDecimal result = invoice...
Execute and get the output of a shell command in node.js
... a node.js, I'd like to find a way to obtain the output of a Unix terminal command. Is there any way to do this?
5 Answers
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How to create a database from shell command?
...her solution that would allow me to create database with a help of a shell command. Any hints?
8 Answers
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Good Haskell source to read and learn from [closed]
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What I recommend.
Read code by people from different grad schools in the 1990s
Oxford style
Glasgow style or (this)
Chalmers style (or this)
York style
Portland style or OGI style (or this)
Utrecht style
Yale style
Special case: CM...
Best approach for GPGPU/CUDA/OpenCL in Java?
General-purpose computing on graphics processing units ( GPGPU ) is a very attractive concept to harness the power of the GPU for any kind of computing.
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Convert UTC date time to local date time
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How do you redirect HTTPS to HTTP?
...you stop paying, people who bookmarked the https links will not be able to come through.
– Stephen Cheng
Sep 9 '14 at 16:47
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Best cross-browser method to capture CTRL+S with JQuery?
...a form. Is there a good cross-browser way of capturing the Ctrl + S key combination and submit my form?
16 Answers
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