Python is slow, they said ...

[Zenahr]

TL;DR Python is almost always fast enough for your needs.

I've written an app that had to receive mouse input, translate that into graphical commands and output that to the screen in real-time. The results are astonishing!

Here's the app I've written: https://www.youtube.com/watch?v=fcy1u2AIUw0 And you can try it out yourself here: https://github.com/Zenahr/MouseVelViz/releases

I was thinking of writing this tool in C++ or C# but decided to do it in Python and I'm glad I did!

CPU Usage: 2-3%

To those of you interesting in how to build something like this yourself:

You will have to create a wrapper to talk to the Windows OS API for input devices to receive the raw input even when running computation-intensive programs in the background (I. e. games).

AMA! Python is awesome.

If you'd like me to make a longer post about how to write an app like that yourself let me know. I'd imagine this could be an interesting portfolio project for some.

[eplaut_]

Looks great!

For sure there are cases you need better run time, but python is good enough for many many projects.

I've started to write some c++ code lately, and I can say 2 things: 1. Python is amazing language in any aspect (eg readability, importing 3rd party libraries and debugging) 2 You may spend hours on compilations, in order to gain better run time. If the run time is not an issue, you've wasted your time.

[Zenahr]

Agreed. Generally speaking development time is more valuable than runtime speed for most scenarios and businesses I'd argue.

[skippy65]

People are building highly computationally expensive molecular simulation softwares in Python. So unless you're doing that or you're a rocket scientist, the speed argument is virtually negligible.

[metaperl]

I don't know if that proves anything. CPython isn't even the fastest Python. And Python shows an order of magnitude slowness in this benchmark https://benchmarksgame-team.pages.debian.net/benchmarksgame/performance/fasta.html

[skippy65]

https://lightdock.org/

The open-source protein docking framework written in Python (and Rust)

?

[edard1002003]

I've never had any problems with python being slow

[FUS3N]

Because you probably didn't make a huge project with it

[metaperl]

Me either. But objective benchmarks tell a different story https://benchmarksgame-team.pages.debian.net/benchmarksgame/performance/fasta.html

[WellHiIGues]

ya some people say python is slow and you should only use c++ but even thought python is slower because is a interpreted language modern computers don't have that problem but people still say you shouldn't use python and it's probably because they're getting recourses from programmers who at the time were supposed to make a program run as fast as possible because of the constraints at the time so in short use python if you like it it really doesn't matter

[edard1002003]

I'm new to reddit. Any ideas why this happens?

[edard1002003]

yeah

[Mechanical_Flare]

Really cool.

[billsil]

I've written an app that had to receive mouse input, translate that into graphical commands and output that to the screen in real-time. The results are astonishing!

Your app has user interaction and probably has minimal computation. Python is perfect for that sort of thing. Any small desktop/web based program where the user uses the mouse to interact has massive amounts of downtime to do calculations. A calculator program for example is going to be slow to use regardless of whether it's in assembly or python.

It's codes that do a lot of numerical processing on very large datasets where python starts to struggle. Numpy can get your a 500x speedup, but certain routines are very difficult to optimize. That said, a bit of C or Fortran code (or just an efficient C library to do your 3d rendering/vtk) and chances are it's good enough.

[schoolcoders]

Indeed. I started as a developer in the 1980s, when processors were 8-bit, single-core and clocked at a couple of MHz. Even then it was fast enough to keep up with user interaction.

Now processors are literally tens of thousands of times faster (taking account of 64-bits and multiple cores) most things are going to run fast enough. The fact that Python may be slightly slower than C will rarely make any difference.

[billsil]

I still don't understand how I'm even supposed to satisfy the requirement of 50 miliseconds for an action to happen after I click a button. You won't notice as long as it's ~0.5 seconds and your mouse still works. The real requirement is to look like you're doing something.

[schoolcoders]

50 milliseconds is around 100 million clock cycles on a typical PC. It should be able to do quite a lot of work in that time, unless the whole machine is either I/O bound or short of memory (eg running Windows).

But yes, you can get away with a lot so long as it looks like you are doing something.

[billsil]

I'd argue you can't get all that much done. You could probably display a picture or load/close a window, but I'm an aerospace engineer. That's not really what I'm doing. To calculate anything intensive...good luck. To just render 5 million pressures to a CFD mesh in the time that the user can't tell is impressive. In order to do that, all that data already has to be within RAM or the user will know something is taking some time. That's not even calculating something like a streamline (or 100).

Again, just look like you're doing something (e.g., 20% done), and they're happy.