the-width-of-a-circle

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#029 Here Lies The Abyss
Static Preview here & get the code here or here

Features

  • there is an option to add 10 custom links
  • you can add an individual blogtitle to the sidebar (added and edited like everything else in the Appearance tab)
  • the top sidebar image is 380px wide and up to 500px in height. The bottom sidebar image is 380x120px. Both will only be resized in width when they’re too big or too small.
  • the circle image in the linkbar is your icon (there’s an option to hide it)
  • the body font size and all the colours are customisable in the Appearance tab
  • there are like and reblog buttons on every post

What else?

  • please note that the images are not included in the theme, you will have to upload your own 
  • needless to say, don’t remove the credit and don’t redistribute as your own
  • and most importantly: enjoy! :3
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THEME #40 BY EVILQUEENEDTHEMES.

Please make sure to reset default settings when installing the theme.

FEATURES:

  • topbar: 4 optional links + home and message.
  • 245 width sidebar image or a 100x100px circle image (an icon for example, it will automatically turn into a circle).
  • 500 or 400px posts.
  • blog title is optional.
  • normal or rounded borders on posts.
  • possibility to change the sidebar, blog title, posts and “small” fonts and fonts sizes from the customization page (no need to edit the code).
  • colorized scrollbar & selection.

Please like if you use/like the theme. Thank you and Enjoy!

STATIC PREVIEW: preview 1 / preview 2

[ C O D E ]

Curves of constant width

                                                    Source

The width of a circle is constant: its diameter.

But the circle is not the only shape that holds this pristine title. For instance let’s look at the Reuleaux triangle

Reuleaux triangle

A Reuleaux triangle is a shape formed from the intersection of three circular disks, each having its center on the boundary of the other two.

The Reuleaux triangle is the first of a sequence of Reuleaux polygons, curves of constant width formed from regular polygons with an odd number of sides.

Some of these curves have been used as the shapes of coins

To drill square holes.

They are not entirely square, their edges are fillets i.e the edges are rounded and not sharp.

This animation offers a good insight as to why that is so.

And in china, apparently on bicycles.

The man Guan Baihua shows his self-made multi-angle-wheel bicycle on May 6, 2009 in Qingdao of Shandong Province, China. Guan Baihua spent 18 months to complete this strange bicycle.


Other shapes of constant width

There are other shapes of constant width beside the Reuleaux triangle ( that has been discussed in this post ), a whole bunch of them really. Do take a look at them. ( links below )

I will leave you guys with my favorite one.


More:

If this post fascinated you, i strongly suggest you check these out. They go in-depth with the mathematics that underlies these curves and talk about other cool stuff:

An animation of non-circular rollers

Shapes and Solids of Constant Width - Numberphile  

Shapes of constant width

Reuleaux Polygons,           


Edit:

For those who are wondering if these are something that one would stumble upon on a regular basis. You may not find perfect ones but similiar ones definitely.

I found mine on a really old BMI calculator thingy. ( not sure what you would call it )

Have fun exploring !

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THEME #28 BY THEMESBYJASONDILAURENTS.

If you have any problem message me here.
Please make sure to reset default settings before installing.

There are many optional features included in this theme. And when I say optional, it means that you can choose to make them appear or not from the appearence section. All you have to do is enable/disable them. SO please read this post carefully.

FEATURES:

  • Searchbox (optional).
  • Sidebar picture width:200px. You have the option to give it a circle shape,it will automatically be resized to 150x150px.
  • 3 navigation icons (home, ask and archive) also optional. If you choose to disable them, the two columns on the left including the icons will disappear and those links (and the pagination) will appear as text under the description.
  • 6 optional links under the “+ MORE”.
  • Pop-up askbox (optional).
  • You can show/hide the blog title.
  • Like and reblog buttons on posts (optional).
  • The right sidebar pictures will be resized automatically to 120x120px. This sidebar is also optional.
  • I also included in this theme the possibility to change the description font and font-size and the posts font and size from the appearence section. You’ll also be able to change the quote font size and include a Google Web Font name. 
  • As usual, colorized scrollbar and selection.
  • All colors are customizable.
  • You can edit it as much as you want but please don’t claim as your own, don’t use as base and don’t remove my credit.

  • Please like if you use/like the theme. Thank you and Enjoy!


How to use the pop-up askbox:

The theme has a pop-up askbox (try it on the preview). It is optional, so if you don’t feel comfortable with it, all you have to do is disable it on the appearence section.

If you want to use the pop-up askbox, you’ll need to enter your url so that it works properly. To do so, go to customize, scrolll down and you’ll see this: “ASKBOX URL”. You’ll have to enter your url without http:// so it will look like this: username.tumblr.com.

Then you have the option to customize the pop-up askbox title, as seen in the preview. Again, you just have to type it on the appearence section, you’ll see “Askbox Title”, here it is.


Since this theme offers a lot of possibilities, I decided to make different static previews to give you some ideas of what you can do.


ALL OPTIONS ENABLED VERSION: {Static Preview} - {Code}
SIMPLE VERSION: {Static Preview}}

A bit of #math  today #circlearea

▼ Reshared Post From Richard Green ▼

Circumference and area of a circle

The circumference of a circle of radius r is given by the formula 2πr, where π is the famous constant whose value is approximately 3.14159265. This graphic by Margaret Nelson illustrates a simple way in which the formula for the circumference can be used to obtain the formula for the area of a circle, πr^2.

The idea is to cut the circle into a large, even number of equal sectors, as if you were slicing up a pizza. These sectors can then be rearranged into an approximately rectangular area. The upper edge of this area is made out of pieces of exactly half of the circumference, and the same is true for the lower edge. Half the circumference is πr, and the width of the area is approximately equal to the radius of the circle, which is r. The area of the roughly rectangular area is the same as the area inside the original circle. This area can be approximated by a rectangle of dimensions πr by r, which would have an area of πr^2. In the limit as the number of sectors tends to infinity, this approximation will converge to the exact value of the area.

Nowadays, formulas like this for area and volume are proved using calculus, but this elegant argument is a much older idea and goes back as far as Archimedes. It is not so important that the circle be cut into an even number of sectors, because an odd number of sectors will still give a good approximation if there are enough sectors.

The picture comes from an article in the February 2014 edition of the Mathematical Association of America’s magazine Math Horizons. The article is an interview by Patrick Honner of the mathematician Steven Strogatz. Strogatz is a professor at Cornell University who likes to cite this proof as a good argument with which to convince people of the beauty of mathematics.

You can read +Patrick Honner’s article here (http://goo.gl/jZWUTB). His own post about this (https://plus.google.com/+PatrickHonner/posts/dVxDP4Nh8t7) includes a picture of the rearrangement of sectors of an actual pizza.

#mathematics

http://click-to-read-mo.re/p/7F9s/533fa796

THEME #24 BY JASONDILAURENTS / THEMESBYJASONDILAURENTS.

If you have any problem message me here.

FEATURES:

  • Sidebar image 150x150px if you want to keep the circle shape.
  • Left sidebar background image width 170px x the size you want (depending on your screen resolution), the one I used is 170 x 907px.
  • Circle navigation links with numbers in them. Rotation + link title on hover (just try it on the preview to see what I mean). You can pick a different color for each circle.
  • 3 navigation links + 7 optional custom links.
  • Hover tags.
  • All colours are customizable (which means there are a lot of options on the appearance section).
  • As usual colorized scrollbar and selection.


Please note that THE PICTURES ARE NOT INCLUDED in the theme. I only made them for the preview.

You can edit it as much as you want but please don’t claim as your own, don’t use as base and don’t remove my credit.

Please like if you use/like the theme. Thank you and Enjoy!


{Static Preview} - {Code}
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IN ONE YEAR, On August 21, 2017, a total solar eclipse will stretch across the entire width of the United States . Link goes to NASA’s animation – black circle shows the path of total eclipse.

Theme 18 ↬ Lucky

Preview - Code

F E A T U R E S

↬250px/400px/500px post

↬Up to 2 custom links (Option for extra links, learn how to here)

↬optional monochrome posts

↬option to show tags

↬option to show sources

↬option to show captions

↬auto resize sidebar image (width 150px)

↬sidebar image can be defaulted aspect ratio, circle, or hidden

↬long sidebar approximately 300px x 1600px

as long as you’re around that size its fine, the width could be bigger or smaller it really doesnt matter it will auto resize but if the image is a lot smaller than intended, the image is blurry and if the image is a lot larger then some gets cut off

↬posts can be with colour, with translucent colour, or without colour

↬container can be with colour, with translucent colour, or without colour

↬Background can be repeated or cover

↬can have subtitle

Questions || If I haven’t answered your question in 5 weeks || where you can get long side bars||

Theme #14: Fall { Live Preview | Static Preview | Code }

  • 5 custom links
  • 1 column theme
  • auto length description
  • circle sidebar pic (width:250px height:250px)
  • 500px posts
  • small cursor
  • back to top button
  • like/reblog if using
  • don’t remove the credit
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