Archive for March, 2007

Why me? Matlab-LaTex stuff

Since yesterday I am desperately trying to solve a Matlab-LaTex issue, which makes me crazy. This post is only for those nerds out there which dream about Matlab and LaTex instead of chocolate cakes. So here is my problem:

I have a huge datafile, which I visualize via surf in Matlab. It looks colorful, meaningful and hence worth saving as an EPS file for later changes in LaTex via the psfrag package. This works usually very smooth and creates beatiful results. Now, however, due to the huge amount of data in the Matlab image (right one below), the saved EPS file is somewhere between 20-100 MB (!!) and furthermore LaTex doesn’t open it for psfrag. The first thing I did was use a renderer like zbuffer or painters in Matlab and also skip some percentage of the data, which reduced the file size sometimes, but not always (??). I was even able to open the files in LaTex, but psfrag didn’t access the labels in those figures. And sometimes LaTex was even able to acces the labels via psfrag, but then the image had the traces of the grid I used (the white lines in the left image).


I don’t know what to try else. I could of course save the image as JPEG or PDF or whatever and then convert it to an eps figure, than, however, I can’t use psfrag to access the information saved in the images. Another way would be to use the PDF or JPEG images and use a grafic program to insert labels, which than, after saving it as an EPS file, could be accessed by Latex via psfrag. That, however, I will not do, because I have a bunch of pictures, which I wanna have as I want them and I do not compromise. Not in matters of sweets or useless littlenesses like the mentioned here. Another way would be to access the information in JPEG images via imread and than filter the labels out and plot them again via the image command, but all that is not the proper way to solve this problem. There must be a simple way to just save a figure as an EPS file and access it via psfrag in LaTex regardless the huge amount of data in the figure.

This weekend will probably be devoted to this problem and I will probably get extremely angry if some baby wants to but his needs infront of this littleness. So I had to post this in the hope of some smart nerd out there who might just have the smartest way to solve it and hence save my weekend.

PS: For those who wonder what the figure with the strange labels show: It is the Cross-spectra of the streamwise velocity and passive scalar fluctuation across a heated jet at 5 nozzle diameters downstream. The labels are of course not set, but therefore I need psfrag, because Matlab labels just don’t look good enough for my eyes.


Experimental fluid dynamics

Experimentalists know that the ratio of preparation time to the time of performed experiments which are useful is quite high. This can be anticipated from the following two pictures, which show the needed equipment for a flow vizualisation (a simple not much saying image). I had to drink several cups of coffee until I found the right amount of cream or milk to get a nice image of the large scale (the rotating structure) and small scale (the mixing of the concentration) mixing. I couldn’t sleep the whole night and was quite active the following day.


Now it is much more clearer, that nice fluid dynamical images in laboratories do not just appear, one has hard to try to capture it.

Fruits as chocolate replacement, part 2

After my first attempt to start a healthy life and to reduce the amount of sweets consumed during a day I bought the following fruits:


The item on the right side is a well-known member of our family. Since my childhood I always tried to eat a pomegranate without loosing one of its seeds. My parents told me that I would never be able to eat it without loosing one of its seeds, and since then I have never succeeded. Nevertheless I keep trying. The item on the left side is a fruit I never ate before. I still don’t know its name, but it tastes similar to a honey melon, but is much more expensive (30 SEK for one item as big as an appel). Does anyone know what it is?

Fontanelles and reflexion

I have three younger siblings and hence I know that babies do not have a fully developed skull, but rather have a skull consisting of slightly movable fontanelles. I also mentioned the usefulness of these fontanelles in regard of the imaginary relaminarization process during the delivery. Last but not least Family Guy taught me that babies might have a dent and that those can’t be used as an ashtray, but see for your self:

Despite all this I got scared today, when I came home and saw that the dent was much bigger than usual. Additionally our little son was screaming/crying more than usual (although unbelivable, it is possible) and both parents were perplexed and we had to call both grandmothers of our son to ask for help. The result is, that we worry too much and that we should calm down. Babies are a mystery and they neither like to be shaked, nor stirred. Although both help to mix a flow and to silence a baby it is not healthy and can have serious consequences as I was told today, so: no more shaking. Also my attempt to record a timeseries of him crying has come to an end, because it became more and more complicated to hold him still while crying in order not to introduce any falsifying signals. I have to find something else to do with him, because most things I try (although they seem to work fine on the large scales, I do not know what I might cause on the small scales) are somehow work related and I should hang out with some normal (do they exist? and if so where can one find them?) daddies to learn what to do with babies. I am screwed, or am I?

2 Swedish ad classics

Both are maybe known to all of you, but they are still two classics, which can’t be seen often enough.

PS: Remember to change to summer time.

Sad day, but they found me!

I had a bad day yesterday. Threw the towel after realising how less I knew and I how much I thought I would be able to do. Sad as I was I went to COOP and bought an emergency package, namely a baguette, two Nutella and a new ice cream flavour I haven’t tasted before. I finished one Nutella can and the baguette, but didn’t managed to finish the ice cream. My wife was waiting for me; she thought I would cook something for her, because little son was crying the whole day and she couldn’t cook for herself. So, kind as I am, I put some oil and some Indian convenience food in a pot and went in my room to have my son in one arm and try to eat the ice cream with my other. After seeing smoke coming out of the kitchen I found what can be seen on the right image below. My wife refused to eat what I cooked for her with love just because it looks a little bit burnt. You can’t do things right if you are married. 🙂


Today everything looks a little bit more bright. This morning a first cousin living in Tasmania visited my parents in Germany and we spoke via MSN. I haven’t seen or spoken to him since I started my undergraduate studies, almost a decade ago. Than this evening I got an email from another first cousin to whom I also haven’t spoken or whom haven’t seen for more than a decade. He on the other hand lives in Van, at the border to Azerbaijan. Even though I hate MSN and computers I was quite happy to see two of my cousins after such a long time again. Luckily my mother has 10 siblings, so there is a chance to find some other cousins after a long time.

Crosspost from Alex’s blog

Almost every student of fluid mechanics knows the Album of Fluid Motion by Milton Van Dyke.

A book with exactly the same title is available since 2003 with much more beautiful images, see for your self.
Alex drew my attention towards the Russian translation of the classical book, which can be accessed online. See the post by Alex.

March 2007
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