Sorites Paradox
The word "supercomputer" is vague, like a heap of sand in Sorites Paradox.
A couple of hardware failure is not a big deal. A supercomputer is still a supercomputer. And, even if one-third of compute nodes were shut down because of the escalating energy cost, it would still be a supercomputer. What about losing half of the capacity? Where is the borderline between a supercomputer and a non-supercomputer?
Wikipedia: Sorites Paradox
Kanizsa triangle
Sometimes, what we see or perceive in life is not actually what is there.
The Kanizsa triangle is a classic optical illusion that consists of three pac-man-like shapes arranged in a triangle. Even though there isn't a triangle, our brain thinks there is.
Wikipedia: Illusory contours
Nelson Molina
Finding joy in day-to-day tasks would be more important than the technical skills on the resume. I found an interesting story about Nelson Molina, who worked as a sanitation worker for over 30 years in New York City.
"Nelson Molina spent 34 years as a garbage man in New York City. He salvaged over 50,000 items from the garbage and put them on display in what he calls a "secret museum" in Manhattan. He hopes the city will turn it into a real museum soon." -- CNN
Also, this YouTube video "Treasures in the Trash" from the 60 Second Docs is wonderful.
Capoeira
A few days ago, on a weekend, I was hanging out with my two kids around the village office, and there was a small group of people practicing Capoeira on the stage in the courtyard. They were playing unique instruments, singing, and dancing, but at the same time, simulating fights, which was eye-grabbing.
There was no audience except us(my kids and me), and we enjoyed watching it. I thought that the two elements(dance and martial art) are very different and combining these two have lead to a unique and innovative creation that naturally gets people together.
FRC
The term "FRC" in freediving stands for "functional residual capacity," which refers to the volume of air that remains in the lungs after a normal exhalation.
python
Python's enumerate() object is returned in a key-value pair format. The key is
the corresponding index of each item and the value is the items.
>>> my_array = [ 'dog', 'cat', 'fox']
>>> print(list(enumerate(my_array)))
[(0, 'dog'), (1, 'cat'), (2, 'fox')]
>>> for n, item in enumerate(my_array):
... print(f'{str(n)} : {item}')
...
0 : dog
1 : cat
2 : fox
A binary number starts with 0b and a hex number starts with 0x.
>>> bin(28) # decimal to binary
'0b11100'
>>> hex(28) # decimal to hex(hexadecimal)
'0x1c'
>>> int('0b11100', 2) # binary to decimal
28
>>> int('0x1c', 16) # hex to decimal
28
tar
Extract a specific file from a tar.gz file
# Print the list of the files in the tar.gz and find the path of the file
tar ztf data_a.tar.gz
# Extract the file
tar zxvf data_a.tar.gz data_a/datetime/data-1/data-1-a-b.tif
# Extract the directory
tar zxvf data_a.tar.gz data_a/datetime/data-1
# -x: instructs tar to extract files.
# -f: specifies filename / tarball name.
# -v: Verbose (show progress while extracting files).
# -z: filter archive through gzip, use to decompress .gz files.
# -t: List the contents of an archive
awk
Print a matched line with a specific delimiter (e.g. ,)
# Check out the matched line
grep comp01-mg /etc/hosts
192.168.1.101 comp01-mg.mydomain.com comp01-mg
# Print the line as "ip,hostname,hostname.domain"
awk '/comp01-mg/ {print $1,$3,$2}' OFS="," /etc/hosts
192.168.1.101,comp01-mg,comp01-mg.mydomain.com
iDRAC
"Access Error: 400 -- Bad Request."
Sometimes, iDRAC webui beomes inaccessible with FQDN, showing this error message, "Access Error: 400 -- Bad Request." It seems like a bug in a particular iDRAC version. Here's the workaround, which lets you manually set its FQDN.
racadm set idrac.webserver.ManualDNSentry \
192.168.20.30,hostname-mg,hostname-mg.mydomain.com
# using the awk tip
racadm set idrac.webserver.ManualDNSentry \
$(awk '/comp01-mg/ {print $1,$3,$2}' OFS="," /etc/hosts)