Your website has cool stuff and encourages people to donate for it, but nobody ever gives a penny? Give them something that they get only for a donation, e.g. a link on your website. However, maintaining a link list is tedious, and it’s not really appealing. Therefore, we are proud to present the donations cloud (similar to a tag cloud) concept along with an easy to use WordPress plugin. Read on to learn how you really get some donations, and how to go about it with your WordPress blog.

If you have have a select form element with a size attribute, one common option for the user is to leave it empty (especially in combination with multiple). The problem is, as soon as one or more options are selected, it is quite impossible in most browsers, to not select anything at all. And even if there is a way, it is not easy to accomplish. Try for yourself to deselect all items:

With a little JavaScript magic, we can offer a button to clear the select field:

function nl_clear_select(element)
{
	var opt_length = document.getElementById(element).options.length;
	for (var i = 0; i < opt_length; i++)
		document.getElementById(element).options[i].selected = false;
}

Now try again to clear the select field. Hint: clicking on "Clear selection" will help a lot.

Clear selection

Neat, eh?

Here’s how to get the currently checked value of radio button section. The parameter elementName is the name attribute of the radio input.

function getRadioValue(elementName)
{
	var i, element = document.getElementsByName(elementName);
 
	for (i = 0; i < element.length; i++)
		if (element[i].checked == true)
			return element[i].value;
}

If you put your cash to a bank account, you will want to know how much money you get with a certain amount at a given rate within a given period. Save the following Bash script as /usr/local/bin/loancalc (or something like that), make it executable, and you will be able to calculate the return on your investments with a single one-liner.

#!/bin/bash
 
function calc()
{
	return $(echo "scale=$2; $1" | bc)
}
 
if [ "$1" == "-h" ] || [ "$1" == "--help" ]; then
	echo "$0 calculates the interest loan of a given amount with a given rate for a given duration."
	echo "Usage: $0 AMOUNT RATE DURATION"
	exit 0
fi
 
if [ -z "$3" ]; then
	echo "Please enter the amount, the rate and the duration (in this order)."
	exit 1
fi
 
AMOUNT=$1
ZINS=$2
DURATION=$3
 
echo "Investment: $AMOUNT bucks at a rate of $ZINS% for $DURATION years."
echo "          Loan            Total"
 
for i in $(seq 1 $DURATION); do
	INTERESTLOAN=$(echo "scale=10; ($AMOUNT/100)*$ZINS" | bc)
	AMOUNT=$(echo "scale=10; $AMOUNT+$INTERESTLOAN" | bc)
	printf "Year ${i} %8.2f " $INTERESTLOAN; printf " %14.2f\n" $AMOUNT;
done
 
printf "Final amount: %1.2f bucks.\n" $AMOUNT

For example:

you@yourmachine ~ $ loancalc 3000 3.5 5
Investment: 3000 bucks at a rate of 3.5% for 5 years.
          Loan            Total
Year 1   105.00         3105.00
Year 2   108.68         3213.68
Year 3   112.48         3326.15
Year 4   116.42         3442.57
Year 5   120.49         3563.06
Final amount: 3563.06 bucks.