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Why is the asterisk before the variable name, rather than after the type?
...n to the type:
int* varA, varB; // This is misleading
As @Lundin points out below, const adds even more subtleties to think about. You can entirely sidestep this by declaring one variable per line, which is never ambiguous:
int* varA;
int varB;
The balance between clear code and concise code i...
Avoid trailing zeroes in printf()
...rn 0;
}
The whole point of nDecimals() in this case is to correctly work out the field widths, then format the number using a format string based on that. The test harness main() shows this in action:
40.00000000000000000000 -> 40.000
359.01335000000000263753 -> 359.013
-359.009990000000...
How to globally replace a forward slash in a JavaScript string?
...a global replacement, i.e. it replaces all instances of the matched /. Without the g it only replaces one instance. And if you remove /g you break the regex completely since the last / is the end-delimiter.
– Seldaek
Jan 24 '13 at 8:04
...
Is there a difference between “==” and “is”?
...argv[1];print(tt is "foo", tt == "foo", id(tt)==id("foo"))'| python3 - foo output: False True False.
– ahuigo
Jul 23 '18 at 12:38
...
Why are regular expressions so controversial? [closed]
...ences now. That means you no longer need to count capture groups to figure out that you need $4 or \7. This helps when creating patterns that can be included in further patterns.
Here is an example a relatively numbered capture group:
$dupword = qr{ \b (?: ( \w+ ) (?: \s+ \g{-1} )+ ) \b }xi;
$quo...
Does Swift support reflection?
...wift lab at WWDC, figured I'd share the rest of it. As everybody's figured out, the engineers I spoke with confirmed the reflect() function exists to support the Playground. But you can still have some fun with it :) here i've hacked out a little model serializer using it. Paste it into the Playgrou...
How can I get a count of the total number of digits in a number?
...
Without converting to a string you could try:
Math.Ceiling(Math.Log10(n));
Correction following ysap's comment:
Math.Floor(Math.Log10(n) + 1);
share...
How to check if command line tools is installed
...kg-info=com.apple.pkg.CLTools_Executables
this will return version info, output will be something like this -
package-id: com.apple.pkg.CLTools_Executables
version: 8.2.0.0.1.1480973914
volume: /
location: /
install-time: 1486372375
...
Is there a rule-of-thumb for how to divide a dataset into training and validation sets?
...mputationally intensive).
Assuming you have enough data to do proper held-out test data (rather than cross-validation), the following is an instructive way to get a handle on variances:
Split your data into training and testing (80/20 is indeed a good starting point)
Split the training data into ...
ObservableCollection Doesn't support AddRange method, so I get notified for each item added, besides
...ction"/> is null.</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="index"/> is not in the collection range.</exception>
public void InsertRange(int index, IEnumerable<T> collection)
{
if (collection == null)
thro...