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How to convert an array of strings to an array of floats in numpy?
...list on the map return value if you use map, since map returns an iterator now.)
However, if it's already a numpy array of strings, there's a better way. Use astype().
import numpy as np
x = np.array(['1.1', '2.2', '3.3'])
y = x.astype(np.float)
...
Why is require_once so bad to use?
...ret the code might even make it marginally slower but, that said, I don't know how thorough the internal method is. It might do extra work to ensure no duplicates.
– Oli
Oct 9 '08 at 9:37
...
Differences between ExpandoObject, DynamicObject and dynamic
...ave any use to you as the developer.
When you extend DynamicObject you are now able to provide CUSTOM behavior regarding how you want dynamic dispatch to resolve to data stored internally in your underlying data representation at run-time.
ExpandoObject stores underlying data in a Dictionary, etc. I...
Why is std::map implemented as a red-black tree?
...implementation". Each implementer chooses an implementation. As far as we know, they've all chose RB trees, so presumably this is either for performance or for ease of implementation/maintenance. As I said, the breakpoint for performance might not imply that they think there are more inserts/deletes...
Algorithm to generate a crossword
...
@Kaffeine, yep I know what you mean - I had to throw out these options because even though they could create really good grids, it's too hard to check (read: I couldn't be bothered), and chances are it's just interference anyway.
...
git + LaTeX workflow
...ized part of your work, and it is also easier for version control, as you know what changes have been made to each chapter, instead of having to figure it out from the logs of one big file.
Using Git efficiently:
Use branches!. There is perhaps no better advice I can give. I've found branches to ...
Select first row in each GROUP BY group?
...ndex-only scans is in development for Postgres 14. See here and here.)
For now, there are faster query techniques to substitute for this. In particular if you have a separate table holding unique customers, which is the typical use case. But also if you don't:
Optimize GROUP BY query to retrieve la...
Programming with white text on black background?
...lets the font (the writing) to project to fore and subdues the background. Now ask yourself is it dark on light that does this or light on dark? Here is the key, in that advocates who vouch for similarity with print suggesting that black outshines the white on paper, is blind to the fact that it is ...
Arrays, heap and stack and value types
... │
16 └───────────────────┘
Now if you had three local variables in a function, of types RefType, ValType, and int[], like this:
RefType refType;
ValType valType;
int[] intArray;
then your stack might look like this:
0 ┌───────...
O(nlogn) Algorithm - Find three evenly spaced ones within binary string
...e, we have the list L = [1, 2, 4, 5, 8]. This step is O(n). The problem is now to find an arithmetic progression of length 3 in L, i.e. to find distinct a, b, c in L such that b-a = c-b, or equivalently a+c=2b. For the example above, we want to find the progression (2, 5, 8).
Make a polynomial p wit...