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I measured some samples for Raman spectra (Renishaw). The obtained data are in .wdf and .wxc format. These data can be accessed by WIRE software (Renishaw), which is not open-source/ free. Is there any other way I could read the data?
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(R package to convert raman data in .txt format exported from WiRe 5.2(Renishaw) and FIVE 5.1(WiTec) into the imzML data format).
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,,
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Hi Wisam
HDFS is a distributed file system specially designed to support big data. A block is a piece of data that can be distributed and replicated across multiple datanodes for fault tolerance and load balancing
Best regards,
RHP
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How edge computing can be useful in structured DBMS file systems? can anyone have a paper or article regarding this?
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There's a paper on how to build a timeseries database for edge computing, it might also be interesting to look at a few of the papers cited there:
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System information
  • OS Platform and Distribution (e.g., Linux Ubuntu 18.04): Ubuntu 20.04
  • Python version: 3.6
  • Installed using virtualenv
  • CUDA/cuDNN version: 11.5 / 8.1.0.77
  • GPU model and memory: RTX 3090 24GB nvidia driver 460.39
  • TensorFlow version: 2.4.0 pip install tensorflow-gpu==2.4.0
Describe the problem
Installed cuda 11.2 and cudnn 8.1.0.77. Faced the following problem when I run train.py
Could not load dynamic library 'libcusolver.so.10'; dlerror: libcusolver.so.10: cannot open shared object file
Solved the problem
  • place libcusolver.so.11 in the tensorflow site-packages of the virtual environment created worked properly
  • followed the link to solve the problem
  • Manage a link between libcusolver.so.11 and libcusolver.so.10 using a comand 'sudo ln -s'
$ ln -s /usr/local/cuda/lib64/libcusolver.so.11 ~.virtualenvs/(env name)/lib/python3.6/site-packages/tensorflow/python/libcusolver.so.10
This fixed the problem for me
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better solution
  • list all libcusolver libs in /usr/local/cuda/lib64/
$ ls /usr/local/cuda/lib64/libcusolver.*
  • you should see libcusolver.so, libcusolver.so.11 or 12, and such but not libcusolver.so.10
  • Manage a link between libcusolver.so.11 and libcusolver.so.10 using a comand 'sudo ln -s'
$ sudo ln -s /usr/local/cuda/lib64/libcusolver.so.11 /usr/local/cuda/lib64/libcusolver.so.10
enjoy it
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Some 3D lossy compression software can achieve more than 70% compression, whilst lossless compression achieves less than 20% and needs to be decoded to be able to use it, what will it mean to you/company(blender, unity, animation companies, etc...) to have a lossless compression software that will achieve more than 50% on all types of 3D files(STL, OBJ, AMF, 3MF, FBX, PLY, etc...) that compress the files using succinct data structure thereby no need for decoding of the file?
Definitely by compressing you'll save lots of space and transmitting the file online will consume less bandwidth, hosting the files will be cheaper, etc... well as some might have guessed, I have developed the software.
1. So I just want to know the economic impact of such software would it run in $Millions or Billions?
2. What companies would be interested?
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cheap network with less bandwidth may be used to transfer files
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Hi, everyone,
I just calculated a pure water-box(32 molecules pre-equilibrated by LAMMPS) to learn how to simulate a NVT ensemble by VASP, but unfortunately, I cannot get a converged energy profile(shown as the figure). It keeps increasing! Could anyone provide some suggestions?
Besides, I noticed that it is the potential energy of the Nosé thermostat keeps increasing, while the F or E0 converges well.
Here is my INCAR file:
SYSTEM = Test
LSCALAPACK = .FALSE.
#Start parameters
NPAR = 6
PREC = Normal
LREAL = Auto
ISTART = 0
ICHARG = 2
#Electronic relaxation
ENCUT = 600
ALGO = Fast
NELM = 300
EDIFF = 1E-5
NELMIN = 5
#MD parameters
ISYM = 0
IBRION = 0
POTIM = 0.5
NSW = 30000
TEBEG = 300
IWAVPR = 11
#NVT canonical model
ISIF = 2
MDALGO = 2
SMASS = 0
#DOS related
ISMEAR = 0
SIGMA = 0.05
#Switches
LWAVE = .FALSE.
LCHARG = .FALSE.
IVDW = 11
Thanks a lot.
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Norman Geist , thanks. I did not know the problem of DFT before. I will have a try :)
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With those three different OS at hand, I wanna know how they would differ in terms of 'Process Scheduling', 'Inter-process communication', 'Memory Management', and 'File Systems'. Is it as simple as, process scheduling for Linux is done with Completely Fair Scheduler (CFS), while Windows uses ?? and Solaris with ?...…or is there more to it. Someone can help on how I would do it for the others (IPC, etc.) ?
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How can we use IPFS with BlockChains to solve different problems.
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IPFS and blockchains may work together well because of the similarity in their structure. In reality, Juan Benet, the founder of IPFS calls this a “ great marriage. ”IPFS is one of a few projects that are part of a community called Protocol Labs, which was also created by Benet. Some IPFS-related projects from Protocol Labs are IPLD (Inter-Planetary Linked Data), and Filecoin. IPLD is a paradigm of distributed data systems such as blockchains. This model allows for easy storage and access to data from blockchain through IPFS. Users willing to store IPFS data will receive Filecoin in return. IPLD allows users to seamlessly interact with multiple blockchains and has been integrated with Ethereum and Bitcoin. In short, IPFS connects all these different blockchains in a way that’s similar to how the web connects all these websites together. The same way that you can drop a link on one page that links to another page, you can drop a link in ethereum [for example] that links to zcash and IPFS can resolve all of that. — Juan Benet
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Consider a configuration where the name nodes have plenty of memory and storage matching the data nodes in a Hadoop cluster.  There are 2 Name nodes. Can the name nodes also be configured as Data nodes?  
i assume if the Name nodes are virtualized, the answer is yes. Either way, I like to know what others have done in this type of situation.
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I think yes
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What id diff. b/w Distributed file systems and distributed database?
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Both are same : store data indifferent location, also maintain replication for fail safe data, they have index for quick access, etc;
They differ by the way you can access or querying; they differ by data format u receive;
The fact is : database has to be on top of a file system;
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I want to log user activity in a way to determine how they access their files on daily basis. For example, student have book in pdf and he read this file and other files during learning process. Log data will be used to model of users. Any ideas or suggestions are welcome, it would be best if there is some built in feature or tools inside Operating system so user stay unaware of tracking their behavior.
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Hi Goran,
Your best option is creating a windows service (.net) and using FileSystemWatcher class for file monitoring. It can be used to monitor network shares also. Anyway, as Rivalino said it can also be done creating file minifilter driver which resides in kernel space or try to use API hooking using Microsoft Detours package.
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The file system makes a difference!
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If its a straight binary dump of a data structure, the first difference you may encounter is endianess. It is straightforward to flip endianess. Unfortunately there are still some postprocessing applications (e.g. visualisation) that need big endian even on same system.
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Is there any difference between them?
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Dear Paramjit Kourç,
A distributed database is a database that consists of two or more files located in different sites either on the same network or on entirely different networks. ... A centralized distributed database management system (DDBMS) integrates data logically so it can be managed as if it were all stored in the same location.
Distributed File System (DFS) is a set of client and server services that allow an organization using Microsoft Windows servers to organize manydistributed SMB file shares into a distributed file system.
Regards,
Shafagat
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I'm calculating the lowest-energy triplet state (ISPIN=2, NUPDOWN=2) of a system comprising an organic molecule attached to a silicon surface. After performing an electronic minimization, I'm seeing the following output in my OUTCAR file for this system:
eigenvalue-minimisations : 38300
total energy-change (2. order) :-0.9235746E-04 (-0.2775273E-06)
number of electron 1086.0000388 magnetization 1.9999998
augmentation part -42.1581394 magnetization 0.1063087
The "augmentation part" is registering at roughly -42, which doesn't make a lot of sense to me. Only the last iteration of the minimization is shown above, but this negative value for the "augmentation part" occurs during all self-consistent steps after the initial NELMDL=-5 non-consistent steps. In my previous work, I've never seen this number be negative. I've also only done non-spin-polarized singlet states in the past, so perhaps the above is caused by the spin-polarized triplet nature of the calculation? I'm not sure. Any information on why this occurs and whether it's OK to see this would be greatly appreciated.
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Aqsa Javaid Akhtar
The eigenvalues seem fine. There are a lot of them because this is a large system (1086 electrons), so I'll attach the corresponding OUTCAR file to this comment. The eigenvalues can be found starting at line 3557 for spin channel 1 and at line 18019 for spin channel 2.
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I have tens of thousands of individual scans in proprietary file formats, and I want to make these public. I need a format that is free and open, or to make my own.
Our proprietary software offers a CSV option, but doesn't export all useful data to the file. In addition, the CSV file it creates is more like two spreadsheets, with the second half having the per-channel photon counts.
I've considered using XML because it is both machine and human readable. My only concern is that XML is bloated. XML has the added benefit of being readable over a web browser, and can be quickly converted to almost any language, including JSON.
Microsoft INI format is also machine and human readable, but INI is fairly phased out. Software writers still have full access to INI functions though, so I wonder if this is still a viable format. INI also converts well to object notation.
Both INI and XML could better represent two spreadsheets worth of different-typed content in a single file than a CSV.
What are your thoughts?
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We currently use only ARTAX Spectra, which I believe is Bruker software. The output format is PDZ23, or a CSV file with very little data about the actual device listed in the output. The output CSV files are two-block files, with the top block being basic two-column header info. The lower block is per-channel total photon counts.
I'd like a better format, with all pertinent header data listed, and in a machine and human readable form. I really expected there to be a standard format, like we have with state and federal water well and climate data, but I don't see anything like that on the internet.
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I have tried reorienting and fixing the following MnI(6,6'-morpholino-2,2'-bipyridine)(CO)3(acetonitrile) complex such that it would optimize in gaussian and no matter what I do to it I always get the same error:
Error in internal coordinate system.
Error termination via Lnk1e in /share/apps/gaussian/g09/l103.exe at Thu Dec 20 16:57:56 2018.
Can someone suggest a method to fixing up my input file such that this error will not occur?
I will include the input and output files for this system with my question so feel free to browse them and see if there are any major corrections that I can make.
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The way Gaussian handles coordinates internally by default has issues when three consecutive atoms are arranged linearly. And your structure contains a lot of such groups.
There are a few ways around this: the easiest is adding the "cartesian" keyword – as mentioned –, which should be fine for most cases, unless you want to fix coordinates or run partial optimisations.
Other ways are adding "dummy" atoms perpendicular to the linear groups, or just reordering the Z-matrix to avoid having three linear atoms in a row in the definition of the geometry.
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I have a modeled structure of RNA with 25 nts. I have renamed the atoms as per the rtp file of the amber99sb-ildn force field. All the steps upto energy minimisation ran without any error. The equillibration step with NVT of 200ps is running extremely slow. I have already run a protein (90 aa long) simulation with exact same parameters which completed NVT in 10 mins. I have no clue where things are going wrong.
p.s. I found it odd that the topol.top file generating after the command: gmx pdb2gmx -f rna.pdb -o rna.gro (with -ff amber99sb-ildn and -water tip4p) is showing system name as 'protein'!
The last few lines of the topol.top file is:
[ system ]
; Name
Protein
[ molecules ]
; Compound #mols
RNA_chain_A 1
Due to this rna_solv_ions.gro shows system name as 'Protein in water'
I don't know if it is relevant to the problem but I found this odd. As if, pdb2gmx cannot recognize my pdb file as a proper RNA molecule!
Kindly help me to understand the issue and resolve it.
Thanks in advance.
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Justin Lemkul Thank you so much for your response. It was the hardware which made the difference. Its running fine now. Though, thanks once again for your insight.
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Java is intended to be used in networked/distributed environments. Toward that end, a lot of emphasis has been placed on security. Java enables the construction of virus-free, tamper-free systems. ...Source: Core Java 10th edition....
The main problem is the fact that malicious code can cause its damage because it has gained unauthorized access to system resources. For example, a virus program might gather private information, such as credit card numbers, bank account balances, and passwords, by searching the contents of your computer’s local file system. In order for Java to enable programs to be safely downloaded and executed on the client computer, it was necessary to prevent them from launching such an attack. Java achieved this protection by enabling you to confine an application to the Java execution environment and prevent it from accessing other parts of the computer. ...Source: Java Complete Reference 9th edition....
Python has become popular for business, scientific, and academic applications and is very suitable for the beginning programmer. There are many reasons for the success of Python. Python has a much simpler and cleaner syntax than other popular languages such as Java, C, and C++, which makes it easier to learn. The Python programs in an interactive environment, which encourages
experimentation and rapid turnaround. Python is also very portable between computer systems. The same Python program will run, without change, on Windows, UNIX, Linux, and Macintosh. ....Source: Phyton for Everyone 2nd edition....
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I have recently gained interest in big data/data mining, and have been reading up on my own. When I surfed through Internet about it, I found mechanisms like map-reduce jobs,distributed file system etc. 
I want to know what are the major algorithms that are used in this field for real time problems.
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Put Big Data into context in real time
"Smart cities, plants, and machines rely on smart analytics to put big data into context in real time and optimize decision-making. Powering today’s analytics tools are advanced algorithms, artificial intelligence (AI), machine learning, and digital twins that pull disorganized, disconnected, and “dark” (captured but unused) data into the mix of available information and make it actionable.
Elevating industrial intelligence
Strategic algorithms and cognitive computing improve operational acuity. Seeq software uses end-user-focused advanced computing algorithms to collect and analyze time-series data from manufacturing systems and process historians in real time. Trending, pattern and limit searches, outlier detection, modeling, and illustrative visualizations are among the capabilities that can be applied directly to the data sources without assistance from data scientists or IT experts..."
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Does/can HDFS manage files across multiple geographically dispersed datacenters? What distributed file systems can be used for this purpose?
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I am trying to perform a simulation of polymer brushes based on PNIPAM with GROMACS code. 
Generating a coordinate file for the system of interest is not problematic, but creating a topology of this non-linear case is complicated (default gromacs tools are dedicated to linear systems like peptide).
Could you recommend the best tool for this problem (topology generation)?
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I have ChIP-Seq data I have been analysing with Homer. I wanted to do Irreproducible Discovery Rate (IDR) analysis on my replicates. So I downloaded the homer-idr and IDR program onto a MAC OS X. I have installed both but IDR will only work when I remove homer-idr. When i have both installed and I launch python from terminal:
>>help('idr')
it gives me the info for homer-idr not IDR. When I remove homer-idr it gives me the correct info for IDR. Both have the same package name if that is my issue.
Does anyone know how to fix this?
Cheers, Ben
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Hi Charlie,
Cheers. Will do!
Ben
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I am actually trying to extract  data from SEC Edgar filings, however I see that building parsers for each form is quite exhausting, in addition not all those filings are of same format even though they are from the same form say for eg. 10k filing. 
I am intrigued if some one can direct me in the right direction.
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Hi Trinadh
You might want to think about textual analysis tools. You could start by running a simple word frequency count to get an idea of the frequency of words within the reports. You could use the linux command line to get you started. Simple tools such as head, tail, wc, grep, tr, sort, sed, cut, uniq and awk can get you a long way in a very short space of time. You could also write some simple Python scripts to carry out these tasks. Python will run on most O/S, is simple to programme and very fast in operation.
However, at the high end of the spectrum, you could use a tool like GATE (written by the University of Sheffield) to perform full textual analysis of any kind of text. You can apply your own list of keywords to the text, or you can use the tool to develop a keyword list based on the contents of the files. It provides you with a POS tagger and many analysis tools which can allow you to understand the sentience of the content of the file. This is a serious tool, and not recommended for amateurs, as there is a steep learning curve. You will also need a thorough understanding of Natural Language Processing to get the best out of it. I have added a link for the GATE software to let you see what it can do.
I hope that helps.
Regards
Bob
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I want to do some waveform analysis in SAC. I am working in rtqt view with displacement records of three component data in ASCII format. Now I want to perform some phase picking and particle motion plotting using SAC. How can I change my data files in SAC format? Any suggestion regarding this conversion would be helpful. 
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Dear Jyotima
Use this program... I think its the best choice ...
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I have downloaded satellite data from TOMS and OMI Sites. It is in .he5 and hdr file format. How can I open such files?
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Hi Tripta,
I think you are talking about .hdf5 file. You can read it by using ENVI software.
I found a link-
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I require a  ready to use VM of Lustre File system, can any one help me for the same? Thanks in advance.
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Linux has an interesting relationship with file systems. Because Linux is open, it tends to be a key development platform both for next-generation file systems and for new, innovative file system ideas. Two interesting recent examples include the massively scalable Ceph and the continuous snapshotting file system nilfs2 (and of course, evolutions in workhorse file systems such as the fourth extended file system [ext4]). It's also an archaeological site for file systems of the past—DOS VFAT, Macintosh(HPFS), VMS ODS-2, and Plan-9's remote file system protocol
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Compression is used for the audio and video file from olden days. In a database how it can be handled in efficient way?
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compression a file with out changing its bit rate is better.......
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Actually, suggestions are needed as to whether it will be applicable for HDFS or any other DFS.
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Can you please write something about PACELC or CAP here? 
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I have been trying to extract meta data from various types of files. I am looking for attributes that are available for any type of file format so that I can use them for clustering. I need suggestions for selecting attributes. Please suggest me some meta data that is available for all kinds of files. If the data are numeric that would be better. Thanks. 
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There are also the so called extended file attributes,
like album, title, duration...
They seem to be added in various file systems.
What also could be done is to compute statistical data
and assign the files to clusters. I faintly remember
that it was possible to recognize componists by the
zipped version of their recorded music.
Regards,
Joachim
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Hi Dear friends,
Is there any difference between cloud file system and cloud storage system?
and what are strategies used in dynamic replication system on cloud storage 
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Cloud storage is the super set of cloud file. 
Example of Cloud Storage : S3, Database as Service, Elastic Block storage 
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I had X.dat file of 1.5GB size while converting to mat file  using the statement
a=dlmread('X.dat',' ');
I got an error as Error using dlmread (line 139)
Mismatch between file and format string.
Trouble reading number from file (row 1u, field
1u) ==>
Is there any other method or there is any delimiter I can use?
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It seems the header file does not tell you much about how the data is stored in your .dat file. Did you check the Matlab file exchange to see if someone already wrote a converter/importer for your data?
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Dear colleagues,
running computational software in parallel on 24 cores has an reasonable data reading time, but by increasing the number of cores up to 80 cores it takes an excruciating time to read data.
my opinion is that if I use parallel file system, I may overcome this matter.
What does PFS do? Does it help me? how much?
Is there any user-friendly, windows OS PFS,and prefered to be open source,and have a good installation guide?
To be honest I couldn't install orangeFS, because of installing servers which needs linux
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Thank you Mahdi, glad to hear it was helpful.
As the additional points raised by Mark and Simon show, creating an efficient parallel system involves a number of subtle details, that was the main message I was trying to get across :) Therefore, you have to keep an open mind when reviewing your performance results. It is not always about cranking up the power.
Just a note, reading about your system and Simon and Mark's comments I wonder if the map-reduce paradigm would work for you. Hadoop is internally taking care of some of the details of juggling files in a distributed file system (http://hadoop.apache.org/). The low level considerations will still hold of course. Just an idea.
All the best
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I recall a paper some time ago that purported to estimate the cost of deleting a file (e.g., a picture).  The argument was that it was cheaper to add storage than to delete files.  I am not able to track this down, but my interest in the question remains. I am aware of studies that estimate the cost of erasure from the point of view of physics, but that isn't what I was looking for. Perhaps as a alternate some sense of consumer behavior with regard to adding storage vs. deleting files would be helpful.
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I met a manager who wanted to delete information older than 5 years from their database with the expectation that their information would be faster. The contractor that met the manager explained that it would involve de-linking references from old records so it would be cheaper to simply invest in newer hardware.
Some systems have an archival mechanism to remove old data; the cost of removing old data would therefore be dependent on whether the system allows the removing of old data or if it needs the software vendor to intervene. For example, one could easily sort an Excel sheet by date and remove old records but with an information system, there could be implications of deleting data from one or more tables without consulting the vendor.
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I am reading a file system related paper. It says a concept "directory indirection". Can anyone explain to me how it works? And also, what is the difference and what are the benefits compared with the classical file system structure?
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I have a HEALPix file and want to convert into normal fits file using a Python. Can anyone show me how this is done in Python?
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Is your initial file a HEALPix FITS file and what do you mean with 'normal' FITS file? Do you want to use a different projection and have a single FITS image extension?
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What are the most fundamental and important papers and books about various kinds of features and their extraction for retrieval and classification of multimodal files containing text, images, audio and video?
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I'm sceptical about the existence of a general
multimedia database theory, because the number
of possibilities is so great. A historical paper
that forebode the internet and multimedia
is "As we may think" by Vannevar Bush.
A strategy that seems reasonable to adopt
in multimedia information systems is to
store the data in their raw, original format
(not in SQL blob fields) somewhere as
files and to store the meta information
in XML (filenames, urls, filetypes, length,
checksum...).
In order to ensure fast access to the
data stored in an XML node, the node's
content could be indexed, e.g. with
a suffix tree. Erasing a node could be
implemented by overwriting the content
in the XML file with blanks. Updating an
XML node would involve deleting the
old content by overwriting and to
append the new content at the end of
the file. The disadvantage is that
indexing is an offline operation wheras
in RDBMS records are indexed immediately.
Regards,
Joachim
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The mapping between semantic data (e.g. file systems and namespaces, databases, object stores) and the devices that store the associated bytes and blocks that compose them has been one-way by design - from semantic data through pointers (e.g. inodes) to blocks of bytes, but the reverse association is rarely used, except for debug. In semantic storage, the storage controllers (and in some cases devices themselves) would know that a block belongs to a specific object, file, table/record/field and this reverse association could be used by new applications for performance optimization, security monitors, and data protection, for example. The idea is not to revolutionize or change storage, but rather allow for reverse mapping so lower-level features can be semantically aware and so new applications like intrusion detection systems can know that block access is suspect, sub-optimal, or requires cache updates.
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Marcos - thanks - can you suggest a specific SRM I should look at?  A paper or open source?
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I find problems in open a 3d image file by Matlab to find a solution for the restoration of the broken the ceramic fragments data that scanned in 3-D scanner. What is the most suitable method for open and read 3d image file by Matlab.
With Best Regards.
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Dear Huda,
I attached two Matlab scripts to import and show a .stl file.
Best regards,
Luca
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I have a .txt file that contains information in the following pattern :
The data is separated in the form of
255,205,0 102,235,39 206,89,165 ....... (that is, 3 uint8 integers separated by commas, and the groups of 3 separated by whitespaces). There are a total of 30*60 = 1800 triplets of numbers separated by commas and the triplets are separated by spaces.
Basically, these are pixel intensities of the 3 channels in an RGB image. I need to store them in a 2 dimensional array such that the first element of each triplet goes into the 1st column, the second element into the 2nd column and the 3rd element into the 3rd column. Effectively, at the end of this operation, I should have a 2 dimensional matrix of 1800x3 size.
Please help me with this. I have attached a sample text file. Thanks in advance.
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@Hossein: numpy.getfromtxt won't work. The input data is not formatted correctly for this type of read. You could, however, reformat the text file to allow for simpler reads, e.g.:
f = open('Image Data.txt')
d = f.read()
f.close()
import re
d = re.sub(' ', '\n', d) # replace white space character with newline
f = open('Image Data Formatted.txt', 'w')
f.write(d)
f.close()
Now you can easily read the tuples into Python with numpy:
my_data = numpy.loadtxt(
fname='Image Data Formatted.txt',
delimiter = ','
)
shape(my_data) # (1800,3)
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How can we design a file system for storing the data? Will it be fine if we make a dummy program in C/C++ with a predefined size of window that accepts input of the file of 5KB and stores in it by maintaining the address table of each data block as well as the hierarchy. I know that in real, file system is a complex thing and more than this dummy program.
If there is any good material or simulation tool available for this then inform the same.
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I would suggest implementing it using a Filesystem in User Space (FUSE) under Linux (see http://fuse.sourceforge.net/). This way you can use normal development tools, debuggers etc. on your code (and it won't lock up your system if you make a mistake). You may also code in languages other than C if you wish. The API is well-documented and there are many example filesystems implemented in this way. You can benchmark performance of your proposed filesystem using well-known tools such as bonnie++, or using real filesystem-sensitive applications such as big databases, squid http proxy etc.
Alternatively you could look at some simulated operating system; maybe something like MOSS (http://www.ontko.com/moss/) might be suitable.