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Java String - See if a string contains only numbers and not letters
...Z]+") == false && text.length() > 2){
to:
if (text.matches("[0-9]+") && text.length() > 2) {
Instead of checking that the string doesn't contain alphabetic characters, check to be sure it contains only numerics.
If you actually want to use the numeric value, use Integer.p...
Python: Get the first character of the first string in a list?
...
You almost had it right. The simplest way is
mylist[0][0] # get the first character from the first item in the list
but
mylist[0][:1] # get up to the first character in the first item in the list
would also work.
You want to end after the first character (character z...
Drawing a dot on HTML5 canvas [duplicate]
...d it. Just draw a rectangle with a width and height of one:
ctx.fillRect(10,10,1,1); // fill in the pixel at (10,10)
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Is it possible to set a number to NaN or infinity?
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– David Heffernan
Mar 25 '11 at 22:30
2
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Accessing items in an collections.OrderedDict by index
...> d.items()
[('foo', 'python'), ('bar', 'spam')]
>>> d.items()[0]
('foo', 'python')
>>> d.items()[1]
('bar', 'spam')
Note for Python 3.X
dict.items would return an iterable dict view object rather than a list. We need to wrap the call onto a list in order to make the indexing...
Could not load file or assembly 'Newtonsoft.Json, Version=4.5.0.0, Culture=neutral, PublicKeyToken=3
...
240
In package manager console execute: Update-Package –reinstall Newtonsoft.Json.
UPDATE
I orig...
Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
...e BIT datatype to represent boolean data. A BIT field's value is either 1, 0, or null.
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How to install Java SDK on CentOS?
...n you read this, the lastest available version may be different.
java-1.7.0-openjdk.x86_64
The above package alone will only install JRE. To also install javac and JDK, the following command will do the trick:
$ yum install java-1.7.0-openjdk*
These packages will be installing (as well as thei...
How is Math.Pow() implemented in .NET Framework?
...king for an efficient approach for calculating a b (say a = 2 and b = 50 ). To start things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
...