SVG: Elliptical arc path

Scalable Vector Graphics allows elliptical paths. Here is rendered image, which can help to realize meaning of the parameters. In case below all elipses and circles are have end points [0,0] and [70.71, 70.71]. Second point is on the circle with radius 100. Arc with small “a” means relative dimensions.

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find a files with -maxdepth and -mindepth

Unix utility find allows many arguments. Here is how one can limit searched directories. Arguments -maxdepth and -mindepth should be used first before let’s say -name or -type.

Let’s created four sub directories to investigate how it works:

$ mkdir -p a/b/c/d

$ find a

$ find a -maxdepth 2

$ find a -maxdepth 2 -mindepth 2

$ find a -mindepth 2

See also find a files with mmin

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Eclipse weather

Weather for Solar eclipse on August 21, 2017 across USA determined how people could experience such rare event.

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Eclipse August 21, 2017

Eclipse on August 21, 2017 will be visible in Minnesota only as a partial eclipse. Total eclipse can be visible south of Minnesota, probably good place to go will be places in Nebraska, Kansas or Missouri. Totality will be around 1 PM CDT.
See more at NASA page SE2017Aug21Tgoogle or interactive map.

Next closest opportunity will be on 4 minutes of totality August 4, 2024 in Indianopolis at 2:08 PM CDT.

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Sexagesimal one character digits

Sexagesimal (base 60) is a numeral system with sixty as its base. In some form with help of decimal digits  is used for measuring time, angles, and geographic coordinates. There are no special symbols for it’s digits like in binary system (0,1) or decimal system (0,1,2,3,4,5,6,7,8,9). For certain application, there could be an option to use existing characters from ASCII table and assign them value of sexagesimal digits [0-9A-Za-x]. Value of such digit is monotonically growing, so it possible to use it for ordering and sorting.

Transformation table  could look like this:

0: 0123456789
3: UVWXYZabcd
4: efghijklmn
5: opqrstuvwx

Here are an example transformations from decimal system into such sexagesimal system with it’s digits defined above:
00:00 -> 00, 01:01 -> 11, 05:10 -> 5A, 10:10 -> AA, 12:10 -> CA, 12:30 -> CU, 12:59 -> Cx, 12:33 -> CX, 23:50 -> No, 10:36 -> Aa, 11:59:59 -> Bxx, 18:30:00 -> IU0.

/* Example of JAVA method for n60 0..59 */
public static char sexagesimal_char(int n60) {
   if (n60 < 10) return (char) (48 + n60);//or (‘0’ + n60)
   if (n60 < 36) return (char) (55 + n60);//65-10 or (‘A’ + n60 – 10)
   return (char) (61 + n60);              //97-36 or (‘a’ + n60 – 36)

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Irish Soda Bread

On Saint Patrick’s day I’ve got surprising gift: Irish Soda Bread. It was gone almost immediately. Very tasty, sweet, a little bit crunchy, just fabulous. Bought at Walmart. Here is link to their recipe.


Nonstick cooking spray
2 cups all-purpose flour
1/4 cup granulated sugar
1 1/2 tsp. baking powder
1 tsp. salt
3/4 tsp. baking soda
3 tbsp. unsalted butter, chilled
1 cup lowfat buttermilk
1/2 cup Nestlé® Raisinets® Milk Chocolate-Covered Raisins
1 tbsp. decorating or coarse sugar



  • Preheat oven to 375° F. Spray 8-inch-round cake pan with nonstick cooking spray.
  • Place flour, granulated sugar, baking powder, salt, and baking soda in food processor; pulse to combine (or, combine ingredients in large bowl).
  • Add butter to food processor; pulse until mixture resembles coarse meal (or, cut butter into pieces, add to bowl and use fingertips to rub until coarse meal forms).
  • Add buttermilk to food processor; pulse to combine (or, make well in center of flour mixture, then add buttermilk and stir dry ingredients into milk to blend).
  • Turn dough onto floured surface; gently knead in Raisinets. Form into ball. Place ball in prepared pan (dough will not come to edges of pan). Sprinkle top with decorating sugar.
  • Bake for 40 minutes or until golden brown. Cool in pan on wire rack for 10 minutes; remove to wire rack. Serve warm or at room temperature.
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Romaine lettuce orange juice smoothie

Simple and easy romaine lettuce orange juice smoothie. See pictures below. There are about 225g of lettuce and 335g of orange juice resulting in two glasses of the smoothie.

Good source of information about food is at including downloadable files.

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md5sum for files in the directory

Here is nice one line solution to generate list of md5sums:
ls *.py | while read f;do md5sum $f;done > /tmp/list1.md5sums

Or oneliner for subdirectory tree:
find . -name "*.py" | while read f;do md5sum $f;done

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Charter 6rd configuration

It’s good to know, that Internet Service Provider CHARTER is getting ready for IPv6. There is a trial program, and here is working Linux configuration:

#edit /etc/config/network
#/etc/init.d/network reload
config interface 'wan6'
        option proto '6rd'
        option peeraddr ''
        option ip6prefix '2602:100::'
        option ip6prefixlen '32'
        option ip4prefixlen '0'

With this configuration it’s possible to browse websites like,,,,, and more, or to ping IPv6 addresses below.

#charter dns6 1
$ ping6 2607:f428:ffff:ffff::1
PING 2607:f428:ffff:ffff::1 (2607:f428:ffff:ffff::1): 56 data bytes
64 bytes from 2607:f428:ffff:ffff::1: seq=0 ttl=59 time=35.329 ms
64 bytes from 2607:f428:ffff:ffff::1: seq=1 ttl=59 time=40.211 ms
64 bytes from 2607:f428:ffff:ffff::1: seq=2 ttl=59 time=38.683 ms

$ ping6
PING (2001:4810::110): 56 data bytes
64 bytes from 2001:4810::110: seq=0 ttl=56 time=109.845 ms
64 bytes from 2001:4810::110: seq=1 ttl=56 time=63.858 ms

$ ping6
PING (2001:718:1:a100::161:30): 56 data bytes
64 bytes from 2001:718:1:a100::161:30: seq=0 ttl=50 time=148.320 ms

$ ping6
PING (2001:718:1:101::6): 56 data bytes
64 bytes from 2001:718:1:101::6: seq=0 ttl=50 time=149.869 ms

#google public DNS6
$ ping6 2001:4860:4860::8888
PING 2001:4860:4860::8888 (2001:4860:4860::8888): 56 data bytes
64 bytes from 2001:4860:4860::8888: seq=0 ttl=54 time=52.621 ms

$ ping6 2001:4860:4860::8844
PING 2001:4860:4860::8844 (2001:4860:4860::8844): 56 data bytes
64 bytes from 2001:4860:4860::8844: seq=0 ttl=54 time=57.752 ms
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Ethernet cables

With improving internet infrastructure, higher speeds are now possible. In case of gigabits per second speed one needs to pay attention to the ethernet cable. Better to choose Cat 5e or even Cat 6. There is nice article What Kind of Ethernet (Cat-5/e/6/a) Cable Should I Use?
Wikipedia: CAT 5, CAT 6

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