sudo apt-get install cowsay
sudo apt-get install cowsay
第一步: 用Chrome浏览器打开 https://wx.qq.com/ 其实在浏览器里面就可以直接用微信了，但是每次都打开浏览器总感觉不爽。因此我们可以做接下来的工作。
Gnuplot is one of the most useful tool for plotting all kinds of figures in Linux system. Here, we give an simple example to plot distribution function with gnuplot. We will plot the function of two kind of molecules A and B in a liquid, along the normal direction (z-axis),ie., as a function of z coordinate. The distribution file are dist_A.dat and dist_B.dat. The value is too different to each other, we plot them with different scale. The details can be found in the script scr_doubleaxis.gnuplot.
To plot, just run
The script is as follows.
继续阅读“Gnuplot Examples (1): Plotting With Double-yaxis”
Suppose we have a file theta.dat which has 1000 lines and each line has a angle value. Its first 10 lines are as follows.
100.35766 105.05182 112.56954 119.66241 125.35966 127.44947 125.47673 121.08910 118.00765 117.77907
How to plot a histogram figure in python with matplotlib with the file theta.dat?
We put this file in the home directory, thus the position is ~/theta.dat.
Then , we plot in Enthought Canopy Graphical Environment! One can download and install it in Software Manager. If we open it, the window looks like this.
A few days ago,I bought a USB Audio card.
I used one night to figure out how to configure the device on Raspberry Pi. I searched a lot of material, and I found many of them are outdated. Lots of people said to changed "/etc/modprobe.d/alsa-base.conf", but in jessie , the file dose not exist.
The files I changed are as follows and these settings works for me:
继续阅读“How to use USB Audio cards on Raspberry Pi 3 (jessie)”
I need to display the qrcode in Linux Terminal. I find there is another convenient tool we can use.
Install qrencode in Debian-based Linux:
sudo apt-get install qrencode
qrencode -o - -t UTF8 '北京欢迎你' qrencode -o - -t UTF8 'hello world'
These commands will display the information in QRcode in terminal.
Sometimes, I need copy some links or text from computer to my smart phone. It's such a bad experience to type all of the contents by myself. So I made a tool in Linux called "Jtext2code", which can generate a QR code according to the text you choose. Use your smart phone application like Scanner to scan the picture generated, you can get the information you choose easily.
It's pretty interesting to get battery information from command line.
What we need first is the files containing the battery information which is stored in
继续阅读“Have fun in Linux command line 02: Get the battery information(Linux Mint)”
On the Raspbian system, when I created a new user with the commands
There is no directory named "gang" under the home directory. When I login as a user (gang) and want to use the
sudo command to create a main directory for myself, I saw the error "gang is not in the sudoers file. This incident will be reported. " This error implies that I have to edit the sudoers file to give myself the privilege to use
sudo. To have the root privilege, I need to do as follows.
继续阅读“Solution for the Error “*** is not in the sudoers file. This incident will be reported. “”