Using variables in if statements if [ “$x” = “valid” ]; then echo “x has the value ‘valid'” fi If you want to do something when they don’t match, replace = with !=. You can read more about string operations and arithmetic operations in their respective documentation. Why do we use quotes around $x? You … Read more
In .NET Core and .NET Framework ≥4.0 there is a generic parse method: Enum.TryParse(“Active”, out StatusEnum myStatus); This also includes C#7’s new inline out variables, so this does the try-parse, conversion to the explicit enum type and initialises+populates the myStatus variable. If you have access to C#7 and the latest .NET this is the best … Read more
For whitespace on both sides, use str.strip: s = ” \t a string example\t ” s = s.strip() For whitespace on the right side, use str.rstrip: s = s.rstrip() For whitespace on the left side, use str.lstrip: s = s.lstrip() You can provide an argument to strip arbitrary characters to any of these functions, like … Read more
The following is an attempt to describe the Ukkonen algorithm by first showing what it does when the string is simple (i.e. does not contain any repeated characters), and then extending it to the full algorithm. First, a few preliminary statements. What we are building, is basically like a search trie. So there is a … Read more
str.count(sub[, start[, end]]) Return the number of non-overlapping occurrences of substring sub in the range [start, end]. Optional arguments start and end are interpreted as in slice notation. >>> sentence=”Mary had a little lamb” >>> sentence.count(‘a’) 4
Ruby has a few methods for changing the case of strings. To convert to lowercase, use downcase: “hello James!”.downcase #=> “hello james!” Similarly, upcase capitalizes every letter and capitalize capitalizes the first letter of the string but lowercases the rest: “hello James!”.upcase #=> “HELLO JAMES!” “hello James!”.capitalize #=> “Hello james!” “hello James!”.titleize #=> “Hello James!” … Read more
A simple answer is: echo ” lol ” | xargs Xargs will do the trimming for you. It’s one command/program, no parameters, returns the trimmed string, easy as that! Note: this doesn’t remove all internal spaces so “foo bar” stays the same; it does NOT become “foobar”. However, multiple spaces will be condensed to single … Read more
List<String> list = ..; String[] array = list.toArray(new String[0]); For example: List<String> list = new ArrayList<String>(); //add some stuff list.add(“android”); list.add(“apple”); String[] stringArray = list.toArray(new String[0]); The toArray() method without passing any argument returns Object[]. So you have to pass an array as an argument, which will be filled with the data from the list, … Read more
Python 3.x makes a clear distinction between the types: str = ‘…’ literals = a sequence of Unicode characters (Latin-1, UCS-2 or UCS-4, depending on the widest character in the string) bytes = b’…’ literals = a sequence of octets (integers between 0 and 255) If you’re familiar with: Java or C#, think of str … Read more
You could use: with open(‘data.txt’, ‘r’) as file: data = file.read().replace(‘\n’, ”) Or if the file content is guaranteed to be one-line with open(‘data.txt’, ‘r’) as file: data = file.read().rstrip()