A Technical I.T./DevOps Blog
(This quiz does not cover object-oriented programming or sorting algorithms. For a Python quiz, see this.)
1. What is a sink in a directed graph?
__________________
Answer: A vertex with no route/edge to another vertex; a terminating vertex. Source: Elements of Programming Interviews in Python
2. What is the difference between a vertex and a node?
…
In the past five years as of 8/30/21,
Cryptocurrency and financial technology appear to have very bright futures. To learn more about cryptocurrency, read these postings. To get a book about cryptocurrency, see this list.
…
Continue reading “Three Companies Grew by 1,000% in Five Years”
Problem scenario
You have a website powered by WordPress. You see a big gulf of space between your widgets/ads and your posting previews. It only happens on one page of previews (not other pages). The ads are too far to the right when the preview doesn’t wrap. Why are your previews not wrapping on one page?
Solution
The problem may be one posting.
…
Continue reading “How Do You Troubleshoot WordPress Posting Previews That Don’t Wrap on One Page?”
Problem scenario
You do not want to install new Python modules. How do you use Python to print out the latest price of Bitcoin?
Solution
Run this program:
import requests
resp = requests.get(“https://api.coindesk.com/v1/bpi/currentprice/USD.json”)
print(resp.json()[’bpi’])
Here is a modified version of the program:
import requests
resp = requests.get(“https://api.coindesk.com/v1/bpi/currentprice/USD.json”)
print(resp.json()[’bpi’][’USD’][’rate’])
If you want to receive free cryptocurrency by just learning more,
…
Problem scenario
You try to run an ant command. But you get this error: ‘Target “release” does not exist in the project “apache-cassandra”‘
What should you do?
Solution
Omit the word “release” when you run the ant command.
…
Problem scenario
You want to listen to a .WAV (or an .mp3) file on your Ubuntu/Debian/Linux Mint machine from the command line. What should you do?
Solution
Run this: sudo apt -y install sox
Run this (but substitute “/play/to” with the path to your file and replace “nameof.wav” with the name of the file you want to listen to): play /path/to/nameof.wav
…
Continue reading “How Do You Play a .WAV File Using Ubuntu?”
Question
The terms provisioner and provider seem similar. How would one be compared versus the other? Are provisioners and providers in Terraform the same? If not, how are they different?
Answer
Provisioners in Terraform run commands and do various things to a given server (e.g., transfer a file, run a shell command, run chef-client commands). (This was taken from page 213 of Terraform: Up &
…
Continue reading “How Are Provisioners Different from Providers in Terraform?”
Question
Attention to details such as terminology can be important in technical writing. When making software, should you use the term build, create, develop, grow, produce or write?
Answer
We think that context matters. It seems that the terms write or build are often ideal when you are describing the process for creating/producing a software product, application or “work.”
Richard Stallman said ‘I think it is ok for authors (please let’s not call them “creators”,
…
Continue reading “Do You Build, Create, Develop, Grow, Produce or Write software?”
Question
You have heard the term “white box computer.” What is it?
Answer
A workstation or server that is not created by a well-recognized brand. Some people refer to plain flavors as “vanilla.” If a data center is getting white-box servers, they are not getting Dell or HP servers. White-box servers are affordable and may compete with the public cloud. Commodity servers are well known for being acceptable for Hadoop.
…
Problem scenario
You run a terraform command. You get ‘unsupported argument aws_key_pair’. You want terraform to create an EC-2 server with a specific key pair. What should you do?
Solution
Don’t use “aws_key_pair”, use “key_name”. The aws_instance section in a .tf file uses a different keyword. (The aws_key_pair is for creating an key-pair in AWS.) Use the “key_name” field for aws_instances like this:
resource “aws_instance” “example” {
ami = “ami-01a1234abcd567”
instance_type = “t2.micro”
key_name = “appleorange”
} …
Continue reading “How Do You Troubleshoot the Terraform Error ‘unsupported argument aws_key_pair’?”