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Removing all non-numeric characters from string in Python
How do we remove all non-numeric characters from a string in Python?
7 Answers
7
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What is stack unwinding?
... char* pleak = new char[1024]; // might be lost => memory leak
std::string s( "hello world" ); // will be properly destructed
if ( x ) throw std::runtime_error( "boom" );
delete [] pleak; // will only get here if x == 0. if x!=0, throw exception
}
int main()
{
try
{
...
Are there any reasons to use private properties in C#?
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I use them if I need to cache a value and want to lazy load it.
private string _password;
private string Password
{
get
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
...
How to initialize all members of an array to the same value?
...8(...) STRUCTVAL_32(__VA_ARGS__), STRUCTVAL_16(__VA_ARGS__)
struct Pair { char key[16]; char val[32]; };
struct Pair p_data[] = { STRUCTVAL_48("Key", "Value") };
int a_data[][4] = { STRUCTVAL_48(12, 19, 23, 37) };
macro names are negotiable.
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how to exclude null values in array_agg like in string_agg using postgres?
...s g
GROUP BY g.id
) s
Or, simpler and may be cheaper, using array_to_string which eliminates nulls:
SELECT
g.id,
array_to_string(
array_agg(CASE WHEN g.canonical = 'Y' THEN g.users ELSE NULL END)
, ','
) canonical_users,
array_to_string(
array_agg(CASE ...
To draw an Underline below the TextView in Android
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There are three ways of underling the text in TextView.
SpannableString
setPaintFlags(); of TextView
Html.fromHtml();
Let me explain you all approaches :
1st Approach
For underling the text in TextView you have to use SpannableString
String udata="Underlined Text";
SpannableString con...
In C#, why is String a reference type that behaves like a value type?
A String is a reference type even though it has most of the characteristics of a value type such as being immutable and having == overloaded to compare the text rather than making sure they reference the same object.
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Create Directory if it doesn't exist with Ruby
... system will launch /bin/sh to parse the mkdir -p "foo/bar" string and then the shell will run /bin/mkdir. So you're doing extra work (create the command string, launch /bin/sh to pull it apart again) and some of that extra work leaves you open to shell injection attacks (spend some t...
Regex select all text between tags
... the single/double quote characters with ` in order to put the regexp in a string.
– David Zwart
Sep 14 '18 at 10:58
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Executing multi-line statements in the one-line command-line?
...rehension, lambdas, sys.stdout.write, the "map" builtin, and some creative string interpolation, you can do some powerful one-liners.
The question is, how far do you want to go, and at what point is it not better to write a small .py file which your makefile executes instead?
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