It has been confusing for me what the difference is between the version-vaild-for number (offset 92) and the file change counter (offset 96) in the database file header.
The entries at offsets 92 and 96 were added in later version of the SQLite library.
When an older version modifies the file, it will change the change counter (offset 24), but not adjust the version-valid-for number or the write library version number. So the library version number is no longer correct, because a different version last wrote to the file.
The version-valid-for number allows a new library to detect this case: if the change counter and the version-valid-for number do not match, then the write library version number is outdated, and must be ignored.
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I have been obtaining .zip archives of genome annotation from NCBI (mainly gff files). In order save disk space I prefer not to unzip the archive, but to read these files directly into R using unz(). However, it seems that unz() is unable to extract files from the end of 'large' zip files:
ncbi.zip <- "file_location/name.zip"
files <- unzip(ncbi.zip, list=TRUE)
gff.files <- files$Name[ grep("gff$", files$Name) ]
## this works
gff.128 <- readLines( unz(ncbi.zip, gff.files[128]) )
## this gives an empty data structure (read.table() stops
## with an error saying no lines or similar
gff.129 <- readLines( unz(ncbi.zip, gff.files[129]) )
## there are 31 more gff files after the 129th one.
## no lines are read from any of these.
The zip file itself seems to be fine; I can unzip the specific files using unzip on the command line and unzip -t does not report any errors.
I've tried this with R versions 3.5 (openSuse Leap 15.1), 3.6, and 4.2 (centOS 7) and with more than one zip file and get exactly the same result.
I attached strace to R whilst reading in the 128 and 129th file. In both cases I get a lot of lseek towards the end of file (offset 2845892608, larger than 2^31) to start with. This is where I assume the zip directory can be found. For the 128th file (the one that can be read), I eventually get an lseek to an offset slightly below 2^31, followed by a set of lseeks and reads (that extend beyone 2^31).
For the 129th file, I get the same reads towards the end of the file, but then rather than finding a position within the file I get:
lseek(3, 2845933568, SEEK_SET) = 2845933568
lseek(3, 4294963200, SEEK_SET) = 4294963200
read(3, "", 4096) = 0
lseek(3, 4095, SEEK_CUR) = 4294967295
read(3, "", 4096) = 0
Which is a bit weird since the file itself is only about 2.8 GB. 4294967295, is of course 2^32 - 1.
To me this feels like an integer overflow bug, and I am considering to post a bug report. But am wondering if anyone has seen something similar before or if I am doing something stupid.
Having done what I should have started with (reading the specification for the zip64 format specification), it's actually clear that this is not an integer overflow error.
Zip files contain a central directory at the end of the archive; this contains amongst other things the names of the compressed files and the offset of the compressed data in the zip archive. The offset (and file size fields) are only given 4 bytes each in the standard directory field; when the offset is larger than this it should instead be given in the extra fields section and the value in the standard field should be set to 0xFFFFFFFF. Since this is the offset that gets used when reading the file it seems clear that the problem lies in the parsing of the extra field.
I had a look at the source code for R 4.2.1 and it seems that the problem is due to the way the offset specified in the standard offset field is tested:
if(file_info.uncompressed_size == (ZPOS64_T)(unsigned long)-1)
changing this == 0xFFFFFFFF seems to fix the problem.
I've submitted a bug report to R. Hopefully changing the check will not have any unintended consequences and the issue will be fixed.
Still, I'm curious as to whether anyone else has come across the same issue. Seems a bit unlikely that my experience is unique.
I'm a new user of PARI/GP, and after writing my script, I wanted to make a graph of it. As my function take an integer and return a number, it's closer to a sequence. Actually, I didn't know how to do it, so I read the documentation of PARI/GP, and after that I made some test in order to obtain a graph from a list.
After reading an answer in stackoverflow (Plotting multiple lists in Pari), I wanted to test with the following code:
plothraw([0..200], apply(i->cos(i*3*Pi/200), [0..200]), 0);
But when I do it, it tries to open something on latexit, but then it crash and give me a problem report.
I didn't even know that I had an app named latextit, maybe it was install during the installation of PARI/GP. Anyway, how can I fix this?
PARI/GP definitely doesn't install latexit.
The way hi-res graphics work on the Win32 version of PARI/GP is to write down an Enhanced Metafile (.EMF) in a temp directory and ask the system to
"open" it. When you installed latexit it probably created an association in the registry to let it open .EMF files
i3Pi does not mean what you think, it just creates a new variable with that name. You want i * 3 * Pi instead.
The following constructions both work in my setup
plothraw([0..200], apply(i->cos(i*3*Pi/200), [0..200]), 0);
plothraw([0..200], apply(i->cos(i*3*Pi/200), [0..200]), 1);
(the second one being more readable because a red line is drawn between successive points; I have trouble seeing the few tiny blue dots)
Instead of apply, you can use a direct constructor as in
vector(201, i, cos((i-1) * 3 * Pi / 200))
which of course can be computed more efficiently as
real( powers(exp(3*I*Pi/200), 200) )
(of course, it doesn't matter here, but compare both commands at precision \p10000 or so ...)
I have a daily use case where I need to work with projects on different version of Java (8, 11, ...).
I would like to have it displayed in the right side prompt in my shell (ZSH with Oh-My-Zsh). I know of a dummy way (computationally expensive) to do it (just java --version to var and display it). I would like it to have it cached until I don't source a file (which is a specific project file that sets the new env vars for different java versions).
Do you have any ideas how to do this efficiently?
Br,
Stjepan
The PROMPT and RPROMPT variables can have both static and dynamic parts, so you can set the version there when you source the project file, and it will only be calculated one time. The trick is to get the quoting right.
This line goes in the project file that sets the env variables, somewhere after setting PATH to include the preferred java executable:
RPROMPT="${${=$(java --version)}[1,3]}"
The pieces:
RPROMPT= - variable for the right-side prompt.
"..." - the critical part. Variables in double quotes will be expanded then and there, so the commands within this will only be executed when the project file is sourced.
${...[1,3]} - selects the first three words of the enclosed expression. On my system, java --version returns three lines of data, which is way too big for a prompt; this reduces it to something manageable.
${=...} - splits the enclosed value into words.
$(java --version) - jre version info.
I'm trying to convert pdf to images using this command:
gm convert ./file.pdf -scene 1 thumbs/thumb%02d.jpg
Although I specify -scene argument, it does nothing, as I get output files starting from thumb00.jpg. And I need them to start from thumb01.jpg.
I'm using GraphicsMagick 1.3.12.
What am I doing wrong here?
In order to ensure numbered output files, add the +adjoin option like:
gm convert ./file.pdf -scene 1 +adjoin thumbs/thumb%02d.jpg
This additional requirement was added by GraphicsMagick 1.3.15. It is ok to use the same option for all earlier releases.
There is still an inability to specify the starting scene number. This is a known bug.
Good day. The programs function is to take an equipment number (or none), display that number with a description (or all) in alv, and then run IE03 should the user double click on
Program worked fine in client 110, but in 150 a runtime error happens. This morning I tried to make a new program with a shorter name (only lead I had), activated it (window popped up asking me to activate the previous version as well). That didn't work and now the original doesn't work in either.
The program "SAPLSKBH" is terminating because program line is too long, being 78 chars wide which is too much for the internal table "\FUNCTION=K_KKB_FIELDCAT_MERGE\DATA=L_ABAP_SOURCE[]"
It sounds like you are using REUSE_ALV_GRID_DISPLAY for output, is that correct?
Check you source code; somewhere you have a line that is more than 78 characters. The function K_KKB_FIELDCAT_MERGE takes the source code of your program to produce a structure that corresponds to the table/structure you give it. (In the old days, there was a limit of 78 characters width for a line of ABAP code, and this is an old function module).
You can alternatively build a field catalog yourself in code, rather than use this function.