to your HTML Add class="sortable" to any table you'd like to make sortable Click on the headers to sort Thanks to many, many people for contributions and suggestions. Licenced as X11: http://www.kryogenix.org/code/browser/licence.html This basically means: do what you want with it. */ var stIsIE = /*@cc_on!@*/false; sorttable = { init: function() { // quit if this function has already been called if (arguments.callee.done) return; // flag this function so we don't do the same thing twice arguments.callee.done = true; // kill the timer if (_timer) clearInterval(_timer); if (!document.createElement || !document.getElementsByTagName) return; sorttable.DATE_RE = /^(\d\d?)[\/\.-](\d\d?)[\/\.-]((\d\d)?\d\d)$/; forEach(document.getElementsByTagName('table'), function(table) { if (table.className.search(/\bsortable\b/) != -1) { sorttable.makeSortable(table); } }); }, makeSortable: function(table) { if (table.getElementsByTagName('thead').length == 0) { // table doesn't have a tHead. Since it should have, create one and // put the first table row in it. the = document.createElement('thead'); the.appendChild(table.rows[0]); table.insertBefore(the,table.firstChild); } // Safari doesn't support table.tHead, sigh if (table.tHead == null) table.tHead = table.getElementsByTagName('thead')[0]; if (table.tHead.rows.length != 1) return; // can't cope with two header rows // Sorttable v1 put rows with a class of "sortbottom" at the bottom (as // "total" rows, for example). This is B&R, since what you're supposed // to do is put them in a tfoot. So, if there are sortbottom rows, // for backwards compatibility, move them to tfoot (creating it if needed). sortbottomrows = []; for (var i=0; i
How can you tell how old a tree is without chopping it down and counting its rings?
It turns out that there's some really simple math that you can use to estimate the age of a tree. All you need to know is how big around its trunk is and what kind of tree it is!
Here at Political Calculations, we build tools to solve problems like this! And, after a quick Internet search, we discovered that no one else appears to have already built a tool to solve this kind of math, which means that we'll have a monopoly on tree age calculators on the World Wide Web! Can fame and riches be far behind? Or an intensive investigation by the anti-trust division of the Department of Justice?
Bring it on, we say! Now, let's get to business....
In our tool, enter the circumference of the tree you measured and select which kind of tree it is from our list (if it's not in the list, select a tree that you believe would have a similar growth factor). Then click the "Calculate" button, and we'll give you a pretty good estimate of the age of that tree!
Arboriculturist Jim Skiera offers the following insight for interpreting the results of the math:
"The figures in the chart are taken for forest grown trees. In a landscape setting, where trees are being provided additional care, these figures probably would need to be adjusted to get an accurate estimate. Growth has to do with the location of the tree and the type of care it has received. Trees in the landscape tend to grow faster and develop wider growth rings more quickly because the competition from other trees is usually less and the additional water and fertilizer that is provided by the home owner will also increase growth.
In other words, you need to take into account where the tree you've measured is located. If the tree whose age you're trying to estimate is in your yard or in a park, and not in a forest, our tool will overestimate the age of the tree.
Now for the really cool part. What we've just done for estimating the age of trees, we can do with people too! We'll explain more soon....
Labels: environment, tool
Welcome to the blogosphere's toolchest! Here, unlike other blogs dedicated to analyzing current events, we create easy-to-use, simple tools to do the math related to them so you can get in on the action too! If you would like to learn more about these tools, or if you would like to contribute ideas to develop for this blog, please e-mail us at:
ironman at politicalcalculations
Thanks in advance!
Closing values for previous trading day.
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