The
summation(n, term)function from the higher-order functions lecture adds upterm(1) + ... + term(n). Write a similar function calledproductthat returnsterm(1) * ... * term(n).
This problem is quite easy, we just need to use * instead of +. The logic is similar to summation(n, term) function in the lecture.
Remember to set ans = 1 at first, after all, 0 * any numbers is always equal to 0 🤗
Skip :)
Fill in the blanks in the following function for adding
ato the absolute value ofb, without callingabs. You may not modify any of the provided code other than the two blanks.
This problem is easy if we know that we can bind names to functions. In this problem:
b < 0, a + abs(b) = a - b, so we should use subb > 0, a + abs(b) = a + b, so we should use addSuppose a password is chosen as a concatenation of four lower-case dictionary words, where each word is selected uniformly at random from a dictionary of size 100,000. An example of such a password is
correcthorsebatterystaple. How many bits of entropy does this have?
In order to calculate the bits of entropy, we need to know how many possibilites there.
We can easily know the combinations count are $100000^4$ and the bits of entropy are $log_2 (100000^4)\approx 66\ bit$ 🤗
Most makefiles provide a target called
clean. This isn’t intended to produce a file calledclean, but instead to clean up any files that can be re-built by make. Think of it as a way to “undo” all of the build steps. Implement acleantarget for thepaper.pdfMakefileabove. You will have to make the target phony. You may find thegit ls-filessubcommand useful. A number of other very common make targets are listed here.
Recently I was fine-tuning my deep learning model, and I habitually started to use print to print some key information on the terminal. So my workflow is like:
Soon, I became bored with this workflow (In fact, I kept this for quite a long time.). However, I suddenly forgot to record key information manually. As a result, I had to navigate in the history output of the the terminal slowly.
Use
journalctlon Linux orlog showon macOS to get the super user accesses and commands in the last day. If there aren’t any you can execute some harmless commands such assudo lsand check again.
When I run log show --last 1d, it keeps running for along time. I don’t know how long it make take, so I will just execute harmless sudo ls to check the log.
From what we have seen, we can use some
ps aux | grepcommands to get our jobs’ pids and then kill them, but there are better ways to do it. Start asleep 10000job in a terminal, background it withCtrl-Zand continue its execution withbg. Now usepgrepto find its pid andpkillto kill it without ever typing the pid itself. (Hint: use the-afflags).
Complete
vimtutor. Note: it looks best in a 80x24 (80 columns by 24 lines) terminal window.
It is a tutorial for beginners of vim. I will just put some notes which are not mentioned in course here.
U command: When we press u in normal mode, we can undo the last command. What U does is fixing a whole line.
Ctrl + G: show your location in the file and the file status. Type the linenumber you want to go, then press G, then you are there.
The process of drawing a simple relation graph in python can be broken down into 2 steps.
In this step, we will use the networkx package.
If you are using conda, you can just type conda install networkx
If you are using pip, you can just type pip install networkx
First of all, you need to create a graph.