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MySQL: What's the difference between float and double?
...00002 | 1.6900000000 |
This is using MySQL 6.7
Query:
SELECT
float_1 + float_2 as 'float add',
double_1 + double_2 as 'double add',
decimal_1 + decimal_2 as 'decimal add',
float_1 * float_2 as 'float multiply',
double_1 * double_2 as 'double multiply',
decimal_1 * decim...
java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F…'
...ead:
For a supplementary character, utf8 cannot store the character at all,
while utf8mb4 requires four bytes to store it. Since utf8 cannot store
the character at all, you do not have any supplementary characters in
utf8 columns and you need not worry about converting characters or
losi...
Window.open and pass parameters by post method
...').submit();
</script>
Edit:
To set the values in the form dynamically, you can do like this:
function openWindowWithPost(something, additional, misc) {
var f = document.getElementById('TheForm');
f.something.value = something;
f.more.value = additional;
f.other.value = misc;
win...
How do you convert a byte array to a hexadecimal string, and vice versa?
...
You're using SubString. Doesn't this loop allocate a horrible amount of string objects?
– Wim Coenen
Mar 6 '09 at 16:36
30
...
Accessing items in an collections.OrderedDict by index
...---+---------+
Python 3.6
Python 3 has the same two basic options (list vs generator), but the dict methods return generators by default.
List method:
list(d.values())[0] # "python"
list(d.values())[1] # "spam"
Generator method:
import itertools
next(itertools.islice(d.values(), 0, 1)) # ...
What is the purpose of the Visual Studio Hosting Process?
...ter: it uses a different app.config file. The active one is named yourapp.vshost.exe.config. Watch out for this when you make manual changes to the file.
Another feature it supports that's very visible when you debug your app but isn't mentioned anywhere is what happens to the output produced by ...
How to sort an array by a date property
...e a custom non-enumerable sortBy function using a Schwartzian transform on all arrays :
(function(){
if (typeof Object.defineProperty === 'function'){
try{Object.defineProperty(Array.prototype,'sortBy',{value:sb}); }catch(e){}
}
if (!Array.prototype.sortBy) Array.prototype.sortBy = sb;
...
Django set field value after a form is initialized
...value after the form was submitted, you can use something like:
if form.is_valid():
form.cleaned_data['Email'] = GetEmailString()
Check the referenced docs above for more on using cleaned_data
share
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What does CultureInfo.InvariantCulture mean?
...
Not all cultures use the same format for dates and decimal / currency values.
This will matter for you when you are converting input values (read) that are stored as strings to DateTime, float, double or decimal. It will also ...
Handling applicationDidBecomeActive - “How can a view controller respond to the app becoming Active?
...tionDidBecomeActiveNotification and specify which method that you want to call when that notification gets sent to your application.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(someMethod:)
...