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What's the difference between :: (double colon) and -> (arrow) in PHP?
...ic function sin($angle) {
return ...;
}
}
$result = Math::sin(123);
Also, the :: operator (the Scope Resolution Operator, a.k.a Paamayim Nekudotayim) is used in dynamic context when you invoke a method/property of a parent class:
class Rectangle {
protected $x, $y;
public ...
When to use symbols instead of strings in Ruby?
..., mode: "ascii")
# removed for brevity
end
write(data: 123, file: "test.txt")
freeze to keep as a string and save memory
label = 'My Label'.freeze
share
|
improve this answe...
How to print a number with commas as thousands separators in JavaScript
...ith commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this?
...
How to do exponential and logarithmic curve fitting in Python? I found only polynomial fitting
...ion
from sklearn.preprocessing import FunctionTransformer
np.random.seed(123)
# General Functions
def func_exp(x, a, b, c):
"""Return values from a general exponential function."""
return a * np.exp(b * x) + c
def func_log(x, a, b, c):
"""Return values from a general log function...
Context switches much slower in new linux kernels
..., 0x601ac0, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1
0.000125 futex(0x7f98ce4c0b88, FUTEX_WAKE_PRIVATE, 2147483647) = 0
0.000042 futex(0x601b00, FUTEX_WAKE_PRIVATE, 1) = 1
0.000038 futex(0x601b00, FUTEX_WAKE_PRIVATE, 1) = 1
0.000037 futex(0x601b00, FUTEX_WAKE_PRIVATE, 1) = 1
0.000030 futex(0x...
What are the differences between a pointer variable and a reference variable in C++?
...e of that object becomes the lifetime of the reference.
std::string s1 = "123";
std::string s2 = "456";
std::string s3_copy = s1 + s2;
const std::string& s3_reference = s1 + s2;
In this example s3_copy copies the temporary object that is a result of the concatenation. Whereas s3_reference in...
ReSharper warns: “Static field in generic type”
...tity{ SomeValue = "Bar" };
var thirdInst = new OtherEntity { OtherValue = 123 };
var fourthInst = new OtherEntity { OtherValue = 456 };
var xmlData1 = firstInst.Serialize();
var xmlData2 = secondInst.Serialize();
var xmlData3 = thirdInst.Serialize();
var xmlData4 = fourthInst.Serialize();
In thi...
How do I profile memory usage in Python?
...
123
This one has been answered already here: Python memory profiler
Basically you do something li...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
...alues of 12abc will return abc, value of 1abc will return abc, value of abc123 will return "Not Matched" because the digits were not at the start of the string.
Private Sub simpleRegex()
Dim strPattern As String: strPattern = "^[0-9]{1,2}"
Dim strReplace As String: strReplace = ""
Dim r...
Pass a data.frame column name to a function
...e more about tidyeval here.
library(rlang)
library(tidyverse)
set.seed(123)
df <- data.frame(B = rnorm(10), D = rnorm(10))
Use column names as strings
fun3 <- function(x, ...) {
# capture strings and create variables
dots <- ensyms(...)
# unquote to evaluate inside dplyr verbs
...