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Display number with leading zeros
...n use str.zfill:
print(str(1).zfill(2))
print(str(10).zfill(2))
print(str(100).zfill(2))
prints:
01
10
100
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Pandas percentage of total with groupby
...id': list(range(1, 7)) * 2,
'sales': [np.random.randint(100000, 999999)
for _ in range(12)]})
state_office = df.groupby(['state', 'office_id']).agg({'sales': 'sum'})
# Change: groupby state_office and divide by sum
state_pcts = state_office.groupby(lev...
Remove all child elements of a DOM node in JavaScript
...ById("foo");
myNode.innerHTML = '';
}
<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
<span>Hello</span>
</div>
<button id='doFoo'>Remove via innerHTML</button>
Option 1 B: Clearing textContent
As above, but use .tex...
Group by multiple columns in dplyr, using string vector input
...:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data %>...
setTimeout in for-loop does not print consecutive values [duplicate]
...ctions.
function doSetTimeout(i) {
setTimeout(function() { alert(i); }, 100);
}
for (var i = 1; i <= 2; ++i)
doSetTimeout(i);
If you don't do something like this (and there are other variations on this same idea), then each of the timer handler functions will share the same variable "i". ...
Format number to always show 2 decimal places
...
(Math.round(num * 100) / 100).toFixed(2);
Live Demo
var num1 = "1";
document.getElementById('num1').innerHTML = (Math.round(num1 * 100) / 100).toFixed(2);
var num2 = "1.341";
document.getElementById('num2').innerHTML = (Math.round(...
C++对象布局及多态探索之菱形结构虚继承 - C/C++ - 清泛网 - 专注C/C++及内核技术
...我们先看看这几个类，这是一个典型的菱形继承结构。C100和C101通过虚继承共享同一个父类C041。C110则从C100和C101多重继承而来。
struct C041
{
C041() : c_(0x01) {}
virtual void foo() { c_ = 0x02; }
char c_;
};
struct C100 : public virt...
TypeScript typed array usage
...
You have an error in your syntax here:
this._possessions = new Thing[100]();
This doesn't create an "array of things". To create an array of things, you can simply use the array literal expression:
this._possessions = [];
Of the array constructor if you want to set the length:
this._poss...
What is the size of column of int(11) in mysql in bytes?
...ition of int(2) with no zerofill specified will:
still accept a value of 100
still display a value of 100 when output (not 0 or 00)
the display width will be the width of the largest value being output from the select query.
The only thing the (2) will do is if zerofill is also specified:
a va...
add column to mysql table if it does not exist
...sFieldExisting
$$
CREATE FUNCTION isFieldExisting (table_name_IN VARCHAR(100), field_name_IN VARCHAR(100))
RETURNS INT
RETURN (
SELECT COUNT(COLUMN_NAME)
FROM INFORMATION_SCHEMA.columns
WHERE TABLE_SCHEMA = DATABASE()
AND TABLE_NAME = table_name_IN
AND COLUMN_NAME = field_...