Last Build Date: Thu, 03 Nov 2016 10:21:04 +0000
Thu, 03 Nov 2016 10:21:04 +0000I’ve seriously tried TDD in a real project, writing tests before code and following the red-green-refactor cycle. Short summary: * I believe in TDD now; * training and practice are required to learn TDD, reading books is not enough; * the initial time investment is big. The promise of TDD is that the profit appears […]
Wed, 26 Oct 2016 13:20:52 +0000Rviz A 3d visualization environment for robots. Sounds intriguing and useful, but the first steps in it are painful. In particular, moving anything is surprisingly a very hard task for a novice who doesn’t know about the right way. Now I have enough experience to describe what to do: Moving things in rviz.
Tue, 18 Oct 2016 05:19:02 +0000The Linux command line and other software based on readline library support vi editing mode. After I worked on a new system with the default settings for a while, I noticed that I miss this mode very much. It took some time to remember how I setup it on the main system. Grepping files for […]
Mon, 22 Aug 2016 19:42:51 +0000Based on the article How to Run Your Own Git Server, I’ve constructed a small list for fast git setup for temporary projects. Server: $ mkdir -p /the/server/repository/dir $ cd /the/server/repository/dir $ git init --bare Client: $ cd /my/project/directory $ git init # Note: without --bare $ git add, commit etc $ git push --set-upstream […]
Wed, 20 Apr 2016 11:51:43 +0000I was a speaker at the TeX users meeting in Wuppertal, with the talk “Erfahrung und Vorhersagen für automatisches XML-nach-PDF-Publizieren mit TeX” (experience and prediction for automatical from-XML-to-PDF publishing using TeX). For many years we hear the phrase “TeX can be used for XML publishing”. Unfortunately, due to a few technical problems this phrase is […]
Thu, 21 Jan 2016 08:29:51 +0000python libxml2 dita For correct transformation of DITA files (XML-standard for modular documentation), it is necessary to pull information from DTD (document type definition). In my python code, sometimes I did get this information and sometimes not. Now I’ve tracked the source of instability and corrected the code. Sample python code: import libxml2 import libxsltmod […]
Mon, 21 Dec 2015 16:02:04 +0000The PDF is of some non-standard landscape layout, the printer is an usual A4 printer, the software can’t handle the mix correctly. The solution is to tune the dimensions of the PDF pages manually. First, rotate to the portrain orientation: pdftk non-standard-landscape.pdf cat 2-85E output rotated.pdf I wanted only a few pages (from 2 to […]
Thu, 10 Dec 2015 07:38:55 +0000For XML to DocBook to .docx conversion, I found that “le-tex transpect” framework has solved many technical issues already, so I overcame the “not invented here syndrome” and decided to rely on this tool. To tune the stylesheets for own needs, I created a github copy of the repository: docxtools. To run the stylesheets outside […]
Wed, 30 Sep 2015 12:03:55 +0000In theory, changing content of an Excel file is easy: * Parse XML from the zip-file * Change XML * Save XML into the zip In practice I got the error: >>Von Excel wurde unlesbares Inhalt in … gefunden. Möchten Sie den Inhalt dieser Arbeitsmappe wiederherstellen?< < (English: "Excel found unreadable content...") After long debug, […]
Thu, 09 Jul 2015 12:54:42 +0000In the year 2001 I started to experiment with GUI applications in Python. The experience was summarized and published in the article “A complete Python Tkinter sample application for a long operation“. Now, in the year 2015, a programmer have sent me an updated code. With the minimal changes, which mostly are update of the […]
Fri, 17 Apr 2015 07:20:39 +0000Sometimes I want to read a web page without its design “improvements”. In many case it is enough to switch off css, and in firefox this functionality is built-in. Shift+F7 to get the developer tools. Thanks stackoverflow for the hint.
Fri, 20 Feb 2015 11:04:23 +0000After upgrading the local Linux system, my python paramiko (ssh protocol implementation) program stopped working, with the error message: CTR mode needs counter parameter, not IV Internet search gave no solution. Therefore, it was a time to experiment. A logical consequence from the error message is that somewhere should be used only “IV” or only […]
Mon, 08 Dec 2014 11:42:10 +0000GNU FriBidi is an implementation of the Unicode Bidirectional Algorithm (bidi). There is a Python binding PyFribidi, but it is not complete. What I need is not a visual presentation of a string, but information where direction is changing. This function is not provided by the binding, therefore I’ve made an alternative using ctypes. Download: […]
Mon, 06 Oct 2014 13:37:09 +0000My advice: do use the “second shot” option. At least, I failed to pass the first attempt and had to try again. What was wrong: * I needed time to adapt myself to the testing interface, and probably made something wrong in several first exercises. * A few tasks are a bit unusual and I […]
Mon, 07 Jul 2014 12:19:09 +0000I’ve tried to install a TeX package and got the error message: tlmgr: The TeX Live versions supported by the repository http://ftp.fernuni-hagen.de/ftp-dir/pub/mirrors/www.ctan.org/systems/texlive/tlnet (2014--2014) do not include the version of the local installation (2013) The recommended solution is to install TeX Live 2014, but at the moment I have no time to upgrade. Therefore, I’ve found […]
Mon, 17 Mar 2014 11:51:04 +0000By me, vmware doesn’t start without twicks. A normal rum produces something like: process 3954: Attempt to remove filter function 0xb6ad0690 user data 0xb7896048, but no such filter has been added D-Bus not built with -rdynamic so unable to print a backtrace In my case the solution is to start HAL daemon before running vmware.
Thu, 31 Oct 2013 07:51:00 +0000HTML is the main output format for XML transformations. Every XSLT-processor, including libxslt/libxml2, supports it. But if you transform a libxml2 tree manually, you are in trouble. You can save XML only as XML, not as HTML. A solution is required. My version is not elegant, but works. By the way, the desired functionality is […]
Tue, 22 Oct 2013 06:45:11 +0000The number (and dates) in Excel are float numbers. How these numbers are displyed to an user — as an integer, or with two digits after a point, etc — are defined by the cell format. Unfortunately, xlrd does not support number formatting. It is your task to interpret the format and display the number […]
Fri, 16 Aug 2013 23:08:03 +0000My sequence to grab audiobooks from a cd to hear later on a mp3 player. Grab as mp3: abcde -o mp3 The program makes the job perfectly. But the mp3 player (Samsa Clip+, I like it) is not much smart, or I don’t read manuals carefully. When I return to the folder with an audiobook, […]
Wed, 31 Jul 2013 10:18:33 +0000Sometimes an error and the error message are different things. One of the examples is that my wxpython-program did not want to start after converting to exe using pyinstaller: ImportError: No module named _core_ The two confusing things for me were: * Some time ago the exe-version worked * There is a file wx._core_.pyd in […]