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`levels
...The code is simply setting up a sort of pipeline:
Start with dat$product
Convert it to a factor
Change the levels
Store that in res
Personally, I think that line of code is beautiful ;)
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How can one see the structure of a table in SQLite? [duplicate]
...
Invoke the sqlite3 utility on the database file, and use its special dot commands:
.tables will list tables
.schema [tablename] will show the CREATE statement(s) for a table or tables
There are many other useful builtin dot commands -- see the documentation at http://ww...
For-each over an array in JavaScript
...tly (ES2015+)
See #4.
Create a true array
Other times, you may want to convert an array-like object into a true array. Doing that is surprisingly easy:
Use the slice method of arrays
We can use the slice method of arrays, which like the other methods mentioned above is "intentionally generic"...
What is the easiest way to get the current day of the week in Android?
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Use the Java Calendar class.
Calendar calendar = Calendar.getInstance();
int day = calendar.get(Calendar.DAY_OF_WEEK);
switch (day) {
case Calendar.SUNDAY:
// Current day is Sunday
break;
case Calendar.MONDAY:
// Current day is Monday
break;
case Calen...
Best practices for overriding isEqual: and hash
...ive you do
result = prime * result + var
For objects you use 0 for nil and otherwise their hashcode.
result = prime * result + [var hash];
For booleans you use two different values
result = prime * result + ((var)?1231:1237);
Explanation and Attribution
This is not tcurdt's work, and ...
Possible Loss of Fraction
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....
no new variables on left side of :=
......]int{11,12,14}
colon : is used when you perform the short declaration and assignment for the first time as you are doing in your first statement i.e. myArray :=[...]int{12,14,26}.
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Why is MATLAB so fast in matrix multiplication?
I am making some benchmarks with CUDA, C++, C#, Java, and using MATLAB for verification and matrix generation. When I perform matrix multiplication with MATLAB, 2048x2048 and even bigger matrices are almost instantly multiplied.
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How to get a pixel's x,y coordinate color from an image?
... 4) {
console.log pix[i+3]
}
This will go row by row, so you'd need to convert that into an x,y and either convert the for loop to a direct check or run a conditional inside.
Reading your question again, it looks like you want to be able to get the point that the person clicks on. This can be d...
What does the exclamation mark mean in a Haskell declaration?
...s I try to learn Haskell using a real project to drive it. I don't understand what the exclamation mark in front of each argument means and my books didn't seem to mention it.
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