A “for” statement with a “range” clause iterates through all entries of an array, slice, string or map, or values received on a channel. For each entry it assigns iteration values to corresponding iteration variables and then executes the block. As an example: If you don’t care about the index, you can use _: The … Read more
slice() works like substring() with a few different behaviors. What they have in common: If start equals stop: returns an empty string If stop is omitted: extracts characters to the end of the string If either argument is greater than the string’s length, the string’s length will be used instead. Distinctions of substring(): If start > stop, then substring will swap those 2 arguments. If either argument … Read more
Use splice(startPosition, deleteCount) Show code snippet
it means ‘nothing for the first argument, nothing for the second, and jump by three’. It gets every third item of the sequence sliced. Extended slices is what you want. New in Python 2.3
There are at least 6 (!) ways to clone an array: loop slice Array.from() concat spread operator (FASTEST) map A.map(function(e){return e;}); There has been a huuuge BENCHMARKS thread, providing following information: for blink browsers slice() is the fastest method, concat() is a bit slower, and while loop is 2.4x slower. for other browsers while loop is the fastest method, since those browsers don’t have internal optimizations for slice and concat. This remains … Read more
You can use the substring function: This is the accepted answer, but as per the conversations below, the slice syntax is much clearer:
It’s pretty simple really: There is also the step value, which can be used with any of the above: The key point to remember is that the :stop value represents the first value that is not in the selected slice. So, the difference between stop and start is the number of elements selected (if step is 1, the default). The other feature is that start or stop may be a negative number, which … Read more
2017 Answer – pandas 0.20: .ix is deprecated. Use .loc See the deprecation in the docs .loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element. Let’s assume we have a DataFrame with the following columns:foo, bar, quz, ant, cat, sat, dat. .loc accepts the same slice … Read more
From the code you showed us, the only thing we can tell is that you are trying to create an array from a list that isn’t shaped like a multi-dimensional array. For example or will yield this error message, because the shape of the input list isn’t a (generalised) “box” that can be turned into … Read more
From the code you showed us, the only thing we can tell is that you are trying to create an array from a list that isn’t shaped like a multi-dimensional array. For example or will yield this error message, because the shape of the input list isn’t a (generalised) “box” that can be turned into … Read more