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Segfault while loading images in multiple threads

Hello, I tried to process images in parallel but the load operation results in a Segmentation Fault. Is loading images not thread safe? using Images, FileIO Threads.@threads for path in readdir("img";...

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Autocomplete dataframe columns names not working in jupyter

Hi there, julia newbie here, switching from python :). I am using jupyter and dataframe package. Please, is there a way how to achieve autocomplete columns name in jupyter? ie, having frame =...

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Create vector from Array

If I have an array, how do I create an array containing all values? (Personally, I do not care about the order, but for future references that might be useful as well) 3 posts - 2 participants Read...

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A bit of help with objects and arrays

Hi Everyone I am yet another new Julia language user and I come from a C/Fortran background. So I am pretty weak with some of the object concepts and advanced array syntax. (I will figure it out). I...

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Scope of parametric types and associated error messages

Hello, first post here. Sorry it’s so long. I’m a little confused about the errors I’m getting with different levels of type annotations on a struct with an inner constructor. I have actually solved...

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Exploring package contents

Hi I’m getting into Julia and I don’t yet understamd how I can find out what I can type. For instance I want to read CSV, so I add the CSV package, but then how do I know how to use it? In C# I would...

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How to connect to Cassandra db from Julia

Hello, I am a newbie to julia. I want to access to Cassandra db from julia. I already tried this cqldriver(https://github.com/r3tex/CQLdriver.jl) by adding the package as Pkg.add(“CQLdriver”) but...

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ForwardDiff with function using broadcasting

I am trying to use ForwardDiff to check some analytic gradients for a mse loss and logistic hypothesis function. So just looking at the loss of a single data point we have mse(x) = (1/2)*((y -...

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Performance when using DifferentialEquations.solve repeatedly inside a loop

I am using the split step method to solve the following equation: i \frac{\partial \psi}{\partial t} = -\frac{1}{2} \frac{\partial^2 \psi}{\partial x^2} - |\psi|^2\psi + i \alpha\left(\frac{\partial^3...

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Myid() does not work as expected in @everywhere

I’m running the following code in Visual Studio Code: using Distributed, Plots addprocs(3) @everywhere begin using Plots x = [0, 300] y = [0, 300] p = scatter(x, y) title!(p, "Process: $(myid())")...

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Change Optimization Level in VS Code?

Hi! I changed from Atom to VS Code, and there is a setting option in Atom which allows one to change the optimization level used in Julia when compiling code. Where do I find this setting in Julia? I...

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Convert dataframe to runnable Julia code?

How would I convert a dataframe to Julia code? I have a dataframe containing these in a notebook, and I want Julia code that when run, produces a dataframe with the same contents. 10 rows × 12 columns...

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Confusing Julia & JuliaPro environment variables

What should i add for Julia & JuliaPro in environment variables ( windows 10 ) 2 posts - 2 participants Read full topic

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Where to put files used in src/test?

A couple of my unit tests read sample configs from external files (which also serve as examples for how to write user config files for various functions). Is there a convention on where to put these...

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Graph processing framework

Hi everyone, I am new to Julia as of my final university project. I have been tasked with creating a graph processing framework similar to the Ligra API in C++. Does anybody have any tips or ideas? I...

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Define data-dependent function, various ways

This is a topic that is frequently raised here (I have asked this before). The problem is that of defining a function that will be input as a parameter for a solver, but the function depends on data...

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Recommended serialization interface in Oct 2020: JLD, JLD2,

Obviously a corporation like Mathworks (for all its limitations) shines in its ability to define an official serialization interface: .mat (complexity of .mat versions aside) Is there any plan to do...

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Confusion about type stability of function within a struct

I have a struct called Operators that contains a bunch of functions. However, I can’t get it to be type stable. I have read Type Unstable: Function within a Struct and implemented the solution but it...

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Possible "multiple dispatch" due to API differences between package versions?

hi there, I am wondering whether it is possible to have one function having multiple dispatches simply due to the API changes between package versions. For example, the newest version of ODBC.jl...

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In what way are Julia sets immutable?

If I create a set in Julia, then Julia will tell me that the set is immutable. julia> pets = Set(["dog", "cat", "budgerigar"]) Set{String} with 3 elements: "cat" "budgerigar" "dog" julia>...

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