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Questions tagged [slice]

A slice is a representation of a part of a sequence, usually defined by a reference to the underlying sequence, an index giving the starting position, a length or end position, and optionally a "stride" or "step" value. Please use the tags "object-slicing" for the slicing problem in C++ and "program-slicing" for the analysis technique.

A slice is a representation of a part of a sequence (including, but not limited to, lists, arrays and strings), usually defined by a reference to the underlying sequence, an index giving the starting position, a length or end position, and optionally a "stride" or "step" value.

Further reading:

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Understanding slice notation

I need a good explanation (references are a plus) on Python's slice notation. To me, this notation needs a bit of picking up. It looks extremely powerful, but I haven't quite got my head around it.
Simon
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JavaScript chop/slice/trim off last character in string

I have a string, 12345.00, and I would like it to return 12345.0. I have looked at trim, but it looks like it is only trimming whitespace and slice which I don't see how this would work. Any suggestions?
Phill Pafford
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What is the difference between String.slice and String.substring?

Does anyone know what the difference is between these two methods? String.prototype.slice String.prototype.substring
tmim
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Fastest way to duplicate an array in JavaScript - slice vs. 'for' loop

In order to duplicate an array in JavaScript: which of the following is faster to use? ###Slice method var dup_array = original_array.slice(); ###For loop for(var i = 0, len = original_array.length; i < len; ++i) dup_array[i] =…
Marco Demaio
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Is there a foreach loop in Go?

Is there a foreach construct in the Go language? Can I iterate over a slice or array using a for?
tatsuhirosatou
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Concatenate two slices in Go

I'm trying to combine the slice [1, 2] and the slice [3, 4]. How can I do this in Go? I tried: append([]int{1,2}, []int{3,4}) but got: cannot use []int literal (type []int) as type int in append However, the documentation seems to indicate this is…
Kevin Burke
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Remove last item from array

I have the following array. var arr = [1,0,2]; I would like to remove the last element i.e. 2. I used arr.slice(-1); but it doesn't remove the value.
Prithviraj Mitra
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How to get last items of a list in Python?

I need the last 9 numbers of a list and I'm sure there is a way to do it with slicing, but I can't seem to get it. I can get the first 9 like this: num_list[0:9]
Nope
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What is :: (double colon) in Python when subscripting sequences?

I know that I can use something like string[3:4] to get a substring in Python, but what does the 3 mean in somesequence[::3]?
Aillyn
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How to take column-slices of dataframe in pandas

I load some machine learning data from a CSV file. The first 2 columns are observations and the remaining columns are features. Currently, I do the following: data = pandas.read_csv('mydata.csv') which gives something like: data =…
cpa
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Contains method for a slice

Is there anything similar to a slice.contains(object) method in Go without having to do a search through each element in a slice?
vosmith
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Correct way to initialize empty slice

To declare an empty slice, with a non-fixed size, is it better to do: mySlice1 := make([]int, 0) or: mySlice2 := []int{} Just wondering which one is the correct way.
eouti
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ValueError: setting an array element with a sequence

This Python code: import numpy as p def firstfunction(): UnFilteredDuringExSummaryOfMeansArray = [] MeanOutputHeader=['TestID','ConditionName','FilterType','RRMean','HRMean', …
MedicalMath
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Explanation of [].slice.call in javascript?

I stumbled onto this neat shortcut for converting a DOM NodeList into a regular array, but I must admit, I don't completely understand how it works: [].slice.call(document.querySelectorAll('a'), 0) So it starts with an empty array [], then slice is…
Yansky
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How to slice an array in Bash

Looking the "Array" section in the bash(1) man page, I didn't find a way to slice an array. So I came up with this overly complicated function: #!/bin/bash # @brief: slice a bash array # @arg1: output-name # @arg2: input-name # @args: seq args #…
Chen Levy
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