The accepted answer by John Zwinck is actually false (I just figured this out the hard way!). The problem in the question is a combination of doing “l-value indexing” with numpy’s fancy indexing. The following doc explains exactly this case https://scipy-cookbook.readthedocs.io/items/ViewsVsCopies.html in the section “But fancy indexing does seem to return views sometimes, doesn’t it?” … Read more
Go is free to provide you more capacity than you request. This improves performance by reducing the number of allocations (and possibly copying) that are required. Capacity is just the amount of space reserved before another allocation would be required. If you append 5 elements to this slice, at least in my experiments, the capacity … Read more
As said by Akavall, arrays are hashable. That means they can be used as a key to a map. They are also pass by value. Each time you pass it to a function or assign it to another variable it makes a complete copy of it. They can be serialized by encoding/binary. They also can … Read more
Of course, you can do it – it’s just len is not a field, it’s a method: fn test_length(arr: &[String]){ if arr.len() >= 10 { // Do stuff } } If you only started learning Rust, you should read through the official book – you will also find why &[str] does not make sense (in … Read more
You can’t simply convert []interface{} to []string even if all the values are of concrete type string, because those 2 types have different memory layout / representation. For details see Cannot convert []string to []interface {}. You have to define how you want values of different types to be represented by string values. The easiest … Read more
Here is an alternate solution, though perhaps a bit verbose: func sameStringSlice(x, y []string) bool { if len(x) != len(y) { return false } // create a map of string -> int diff := make(map[string]int, len(x)) for _, _x := range x { // 0 value for int is 0, so just increment a counter … Read more
[:] creates a slice, usually used to get just a part of a list. Without any minimum/maximum index given, it creates a copy of the entire list. Here’s a Python session demonstrating it: >>> a = [1,2,3] >>> b1 = a >>> b2 = a[:] >>> b1.append(50) >>> b2.append(51) >>> a [1, 2, 3, 50] … Read more
Yes, it is possible. Assuming a and b have the same type, the example provided will work just fine. For example: a, b := “second”, “first” fmt.Println(a, b) // Prints “second first” b, a = a, b fmt.Println(a, b) // Prints “first second” Run sample on the playground This is both legal and idiomatic, so … Read more
You can use the indexes to select the rows you want into the appropriate shape. For example: data = np.random.normal(size=(100,2,2,2)) # Creating an array of row-indexes indexes = np.array([np.arange(0,5), np.arange(1,6), np.arange(2,7)]) # data[indexes] will return an element of shape (3,5,2,2,2). Converting # to list happens along axis 0 data_extractions = list(data[indexes]) np.all(data_extractions[1] == data[1:6]) True … Read more
b = a[…, -k:] This is mentioned in the docs.