HDFql is a high-level language to work with HDF5 data, designed to be as simple and powerful as SQL.
Questions tagged [hdfql]
21 questions
4
votes
3 answers
Filter HDF dataset from H5 file using attribute
I have an h5 file containing multiple groups and datasets. Each dataset has associated attributes. I want to find/filter the datasets in this h5 file based upon the respective attribute associated with it.
Example:
dataset1 =cloudy(attribute)…

sumit c
- 93
- 1
- 8
2
votes
0 answers
VSCode/Cmake Tools: add external header library
I want to use a library called HDFQL in a C++ project in VSCode. I am trying to use the extension CMake Tools as much as possible. HDFQL is a header library and usually I would write the following CMakeLists.txt:
cmake_minimum_required(VERSION…

Mr Squid
- 1,196
- 16
- 34
2
votes
2 answers
Is there way to write hdf5 files row by row in Python?
For CSV files we could use
writer = csv.writer(output)
writer.writerow([a, b, c, d])
Is there anything like that for writing Hdf5 files?

SantoshGupta7
- 5,607
- 14
- 58
- 116
2
votes
0 answers
Namespace exists but still getting declaration conflicts?
I am working with the HDFql C++ wrapper library and trying to integrate it with R via Rcpp. I'm an experienced coder in general, but not in C++ specifically. I made another post about trying to resolve an issue with declaration conflicts. The…

mikeck
- 3,534
- 1
- 26
- 39
1
vote
1 answer
Add datetime to HDF5 chunks with HDFql
I have this code to write chunks of arrays to HDF5 and I want to add a timestamp attribute to each chunk or another field with a datetime
using AS.HDFql;
// declare variables
float[,,] traindata = new float[1, 100, 500];
int number;
int i;
//…

Mario
- 13,941
- 20
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- 110
1
vote
3 answers
How to obtain a string type data in a dataset with HDFql in JAVA?
I'm new in HDF5 and HDFql, I'm working in java and I have a .h5 file with several groups, inside each group I have different Datasets, some are floating arrays, which I get as follows.
https://gyazo.com/c10100b327d20a2db8c13f2fd9ab7668
Double[][]…

JavierSO
- 15
- 3
1
vote
1 answer
HDFql Adding Data to Existing Dataset
I want to create a HDF5 file in C++ and dynamically add data to a dataset contained in that file. I have been having some trouble getting this work however, with this minimal example as my current best attempt (based mainly on an answer by…

Mr Squid
- 1,196
- 16
- 34
1
vote
2 answers
HDFql Saving and Loading Images
I am trying to save images from OpenCV to HDF5 using HDFql. Here is a minimal example of what I am trying to achieve (assuming you have an image at /tmp/lena.jpg):
#include
#include
#include…

Mr Squid
- 1,196
- 16
- 34
1
vote
1 answer
Problem loading shared library using dyn.load on R Linux, but equivalent Windows build works fine
I've built a package for interacting with HDFql from R. It relies on the R wrapper and DLLs/SOs provided by HDFql 2.1.0. The packages works perfectly in Windows using the DLLs, but for some reason the HDFql library SOs fail to load in a Linux…

mikeck
- 3,534
- 1
- 26
- 39
1
vote
1 answer
HDFql working with tables
I have some question on the usability of HDFql:
Does HDFql support created of a table where the row are of different type?
How do you append data to the table?
How do you iterate though the row do the table?
The table I want to create will have…

Johan
- 575
- 5
- 21
0
votes
1 answer
Сorrect write from memory in hdfql to dataset
After reading the documentation, I still did not figure out how to write data from memory (variables) to datasets correctly.
For example, with the construction
CREATE TRUNCATE CHUNKED DATASET dsetint AS INT(UNLIMITED), "INSERT INTO dsetint (-1)…

OlegMart
- 5
- 2
0
votes
1 answer
HDFql sequential writing to the structure dataset
I am trying to write a simple structure in hdf5
But I still can't add records to the already created dataset.
The task itself is to store a set of bytes of arbitrary length and its size
void WriteStructToFile(vector> fl_stream)
{
…

OlegMart
- 5
- 2
0
votes
0 answers
importing multiple CSV files into hdf5 using hdfql?
I have to know how to use hdfql to import multiple csv files into one hdf5 file using hdfql method?

M-kh
- 29
- 3
0
votes
0 answers
HDF5 files larger than expected using HDFql
Consider the following code, which simply dumps one million 2-Byte integers into a HDF5 file using HDFql:
std::string filepath = "/tmp/test.h5";
sprintf(script_, "CREATE TRUNCATE FILE %s", filepath.c_str());
HDFql::execute(script_);
sprintf(script_,…

Mr Squid
- 1,196
- 16
- 34
0
votes
2 answers
HDFql Writing Very Slow
I have some code, which iteratively receives data which it dumps to a HDF5 file. Here is a toy example of what I am trying to achieve:
#include
void createHDF(const std::string & filepath)
{
char script_[1024];
sprintf(script_,…

Mr Squid
- 1,196
- 16
- 34