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Generate random 5 characters string
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$rand = substr(md5(microtime()),rand(0,26),5);
Would be my best guess--Unless you're looking for special characters, too:
$seed = str_split('abcdefghijklmnopqrstuvwxyz'
.'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
.'0123456789!@#$%^&*()...
How to position a div in the middle of the screen when the page is bigger than the screen
...it at http://jsfiddle.net/XEUbc/1/
#mydiv {
position:fixed;
top: 50%;
left: 50%;
width:30em;
height:18em;
margin-top: -9em; /*set to a negative number 1/2 of your height*/
margin-left: -15em; /*set to a negative number 1/2 of your width*/
border: 1px solid #ccc;
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R programming: How do I get Euler's number?
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150
The R expression
exp(1)
represents e, and
exp(2)
represents e^2.
This works because exp i...
RestSharp JSON Parameter Posting
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answered Jun 10 '11 at 23:31
John SheehanJohn Sheehan
72.7k2727 gold badges153153 silver badges189189 bronze badges
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How to get all subsets of a set? (powerset)
..., you can just change the range statement to range(1, len(s)+1) to avoid a 0-length combination.
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How to set enum to null
...e for enums that cannot be null by having the FIRST value in the enum (aka 0) be the default value. For example in a case of color None.
public Color myColor = Color.None;
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Get all child views inside LinearLayout at once
...earLayout ll = …
final int childCount = ll.getChildCount();
for (int i = 0; i < childCount; i++) {
View v = ll.getChildAt(i);
// Do something with v.
// …
}
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How to create byte array from HttpPostedFile
... fileData = null;
using (var binaryReader = new BinaryReader(Request.Files[0].InputStream))
{
fileData = binaryReader.ReadBytes(Request.Files[0].ContentLength);
}
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Show an image preview before upload
... // read the image file as a data URL.
reader.readAsDataURL(this.files[0]);
};
Here's a good article on using the File APIs in JavaScript.
The code snippet in the HTML example below filters out images from the user's selection and renders selected files into multiple thumbnail previews:
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Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
... and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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