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A numeric string as array key in PHP
...se a numeric string like "123" as a key in a PHP array, without it being converted to an integer?
11 Answers
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How to organize large R programs?
... different functionality in their own files.
But I don't like R's package system. It's rather hard to use.
I prefer a lightweight alternative, to place a file's functions inside an environment (what every other language calls a "namespace") and attach it. For example, I made a 'util' group of fu...
SFTP in Python? (platform independent)
...s most common use cases to just a few lines of code.
import pysftp
import sys
path = './THETARGETDIRECTORY/' + sys.argv[1] #hard-coded
localpath = sys.argv[1]
host = "THEHOST.com" #hard-coded
password = "THEPASSWORD" #hard-coded
username = "THEUSERNAME" ...
How to read the RGB value of a given pixel in Python?
...
photo = Image.open('IN.jpg') #your image
photo = photo.convert('RGB')
width = photo.size[0] #define W and H
height = photo.size[1]
for y in range(0, height): #each pixel has coordinates
row = ""
for x in range(0, width):
RGB = photo.getpixel((x,y))
R,G,...
Unable to cast object of type 'System.DBNull' to type 'System.String`
... the first case @Alexander mentions -not matching any row- you can rely on Convert.ToString or any other Convert method if you are fine with the value they return when converting from null: empty string for strings, 0 for numeric values, false for boolean, MinValue for DateTime... msdn.microsoft.com...
What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
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I'd probably convert the ticks into a time object like this: SELECT CAST(DATEADD(MILLISECOND, @Ticks/CAST(10000 AS BIGINT), '1900-01-01') AS TIME). The '1900-01-01' date doesn't matter, of course, it's just the third variable required by ...
How to calculate percentage with a SQL statement
...ase you overflow on the 100 multiplication (e.g. Arithmetic overflow error converting expression to data type int), replace it with division in denominator instead: cast((count(*) / (sum(count(*)) over() / 100)) AS DECIMAL(18, 2)) as Percentage
– Nikita G.
Jan ...
How to correctly implement custom iterators and const_iterators?
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They often forget that iterator must convert to const_iterator but not the other way around. Here is a way to do that:
template<class T, class Tag = void>
class IntrusiveSlistIterator
: public std::iterator<std::forward_iterator_tag, T>
{
typ...
Pandas DataFrame column to list [duplicate]
...ta in pandas dataframe has both int64 and float64. When I do df.values, it converts the int64 to float64 and the whole array has dtype of float64. Any clues how to deal with this ?
– ShikharDua
Apr 21 '16 at 21:00
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How can I convert a string to a number in Perl?
I have a string which holds a decimal value in it and I need to convert that string into a floating point variable. So an example of the string I have is "5.45" and I want a floating point equivalent so I can add .1 to it. I have searched around the internet, but I only see how to convert a string t...