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Apply a function to every row of a matrix or a data frame
Suppose I have a n by 2 matrix and a function that takes a 2-vector as one of its arguments. I would like to apply the function to each row of the matrix and get a n-vector. How to do this in R?
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Recursion or Iteration?
...e is recursive call). Tail recursion should be recognized by the compiler and optimized to its iterative counterpart (while maintaining the concise, clear implementation you have in your code).
I would write the algorithm in the way that makes the most sense and is the clearest for the poor sucker...
How do I execute a string containing Python code in Python?
...ting code should generally be the position of last resort: It's slow, ugly and dangerous if it can contain user-entered code. You should always look at alternatives first, such as higher order functions, to see if these can better meet your needs.
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How to reference generic classes and methods in xml documentation
... Not sure what you mean about that. I have never had to add those, and it has always worked for me. Do you have a specific example where it doesn't work? If so, please post it somewhere (or even provide an answer yourself.)
– Lasse V. Karlsen
Oct 26 '11...
How do I use itertools.groupby()?
I haven't been able to find an understandable explanation of how to actually use Python's itertools.groupby() function. What I'm trying to do is this:
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CocoaPods - use specific pod version
... app. I have compilation errors with AFNetworking (current version, 1.2.1) and saw that these didn't exist in the previous version (1.2.0).
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What are the most common naming conventions in C?
...e GTK+ coding convention, which can be summarized as follows:
All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_process().
P...
How to convert ‘false’ to 0 and ‘true’ to 1 in Python
Is there a way to convert true of type unicode to 1 and false of type unicode to 0 (in Python)?
7 Answers
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String output: format or concat in C#?
... what I'm trying to measure.
2. I'm starting the Stopwatch before the loop and stopping it right after, this way I'm not losing precision if the function takes for example 26.4 ticks to execute.
3. The way you divided the result by some iterations was wrong. See what happens if you have 1000 millis...
What's the difference between using “let” and “var”?
...let keyword was introduced to the language was function scope is confusing and was one of the main sources of bugs in JavaScript.
Take a look at this example from another stackoverflow question:
var funcs = [];
// let's create 3 functions
for (var i = 0; i < 3; i++) {
// and store them in fun...