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43 | ␀ | 2021-09-23 20:42:33.247346 | ␀0: Which is actually incorrectly named - it should be "SYMBOL FOR NUL".
Why? "NA" stands for "Not Applicable", but a blank cell in a CSV could represent any number of things of which "Not Applicable" is only one.
Perhaps it would make sense to have a "pretty" mode and a "literal" mode (which would also turn off the clever processing of numbers)?
1. How does tidy-viewer compare with csvlook?
2. Looking at the demo video, there seems to be an odd fixation with "N/A". The CSV spec, AFAIK, doesn't recognize this phrase. I don't understand why someone would expect a quoted string field whose raw characters are "n/a" should be rendered as anything other than n/a (i.e. lowercase and without the quotes). I'm guessing maybe in your workflow you want to use that phrase a lot, but for a tool for the general public I'd not do this kind of interpretation; and I would leave an empty field as empty.
3. tidy-viewer seems to require "unstable library features", or at least ones which were unstable as of Rust 1.48.0 . It would be nice if you could be compatible with older rust distributions/versions.
4. Many systems, especially older ones, especially ones which you access remotely and don't have root privileges on, won't have a rust installation. It would be even more convenient if you could provide binaries with little or no extra dynamic library dependencies, which could be used on older / rustless systems. I realize this is a tall order, however.
5. What about scrolling? The worst part of viewing CSVs is having to handle wide ones which exceed the terminal width, and having decent horizontal as well as vertical scrolling ability. less doesn't cut it, because it doesn't keep the header row, plus it doesn't recognize field widths.
6. tidy-viewer does not seem to support wrapping longer fields onto multiple terminal lines.
7. When the user doesn't specify the color scheme, are you choosing one based on the terminal colors, or are you using absolute color values? I suggest the former.
8. tidy-viewer loads and parses the entire CSV immediately; and, in fact, seems to keep two copies of it in memory at once. This means it cannot be used with large files without thrashing; and even if your CSV does fit in global memory, it will still be kind of unusable, trying to dump gigabytes onto the terminal.
Bottom line: A nice initial effort, but the more serious challenges are yet to be tackled, plus needs to be more robustly cross-platform.
The less(1) command has horizontal scrolling, just invoke it with the -S or --chop-long-lines options or toggle that feature while paging a file.
I agree it would be nicer if less(1) had a user configurable header with a format option to set it to the contents of the first line in a file or stdin or perhaps the most recent line matching a regex to allow for multiple tables and an option to make it scroll horizontally in -S or --chop-long-lines mode.
> How does tidy-viewer compare with csvlook?
The most important issue to me is that csvlook is a much less pleasant viewing experience, but there is also this ...csvlook reads and parses all of the data. Try pushing diamonds.csv to csvlook. When I do it on my machine it takes 15.228 seconds while tv takes 0.0042 seconds. For this reason tv is much faster, but speed is not the goal of the package. tv's purpose is to maximize viewer enjoyment.
2. Looking at the demo video, there seems to be an odd fixation with "N/A". The CSV spec, AFAIK, doesn't recognize this phrase. I don't understand why someone would expect a quoted string field whose raw characters are "n/a" should be rendered as anything other than n/a (i.e. lowercase and without the quotes). I'm guessing maybe in your workflow you want to use that phrase a lot, but for a tool for the general public I'd not do this kind of interpretation; and I would leave an empty field as empty.
I could not say it better than this:
> The norm of treating missing data as NA exists in R (which the developer of this is clearly inspired by based on the GitHub readme.). Pandas in Python is stuck with NaN for numeric types (not quite correct) and "" or None for string types. Personally I like the choice to both explicitly render missing data in colour and to apply NA as a placeholder text to display that colour.
3. tidy-viewer seems to require "unstable library features", or at least ones which were unstable as of Rust 1.48.0 . It would be nice if you could be compatible with older rust distributions/versions.
That is a good point. I also release binaries which I think makes this requirement less needed. What are your thoughts.
4. Many systems, especially older ones, especially ones which you access remotely and don't have root privileges on, won't have a rust installation. It would be even more convenient if you could provide binaries with little or no extra dynamic library dependencies, which could be used on older / rustless systems. I realize this is a tall order, however.
With github actions I auto-build binaries for many OSes. See https://github.com/alexhallam/tv/releases/tag/0.0.13
5. What about scrolling? The worst part of viewing CSVs is having to handle wide ones which exceed the terminal width, and having decent horizontal as well as vertical scrolling ability. less doesn't cut it, because it doesn't keep the header row, plus it doesn't recognize field widths.
Scrolling is nice. To offer scrolling the only option I am aware of is turning this cli into a tui. I made the choice early on to stay chose the more minimal path and stick to a cli. The goal is to be a `column` replacement not a spreadsheet replacement.
6. tidy-viewer does not seem to support wrapping longer fields onto multiple terminal lines.
The goal is to glance at the data as a whole not a cell or fields. If there are cells with long text they get cut at 20 characters. I like this a lot. I would prefer to know that there is a lot of text that I can dig into latter, but when I am glancing at the csv I just want an overall picture. In my view tables of data are data visualizations meaning that I don't have to show everything to understand enough of it.
7. When the user doesn't specify the color scheme, are you choosing one based on the terminal colors, or are you using absolute color values? I suggest the former.
Great question. I want to eventually add the ability for users to make a config file will their own colors. At this time I just have absolute presets. If you are interested I would happily take a contribution that allows users the option to configure tv with some dotfile.
8. tidy-viewer loads and parses the entire CSV immediately; and, in fact, seems to keep two copies of it in memory at once. This means it cannot be used with large files without thrashing; and even if your CSV does fit in global memory, it will still be kind of unusable, trying to dump gigabytes onto the terminal.
That is almost true. tidy-viewer reads the entire csv, but only parses the head. If I knew of a way to get the number of rows and columns of a csv without reading the whole file then I would. I know there is a good deal more room for memory optimization. This is not my strength and I am still learning.
9. Bottom line: A nice initial effort, but the more serious challenges are yet to be tackled, plus needs to be more robustly cross-platform.
Thanks for the compliment. It is still a work in progress.
Does your framework support the idea of pre-parsing the file's content and selecting an appropriate renderer, or is it fairly tied to CSVs?
See https://news.ycombinator.com/showhn.html for details.
Curious, how do you handle formatting on cells with long strings that need to overflow to multiple lines? As soon as you try to optimize the column widths for table length, you start hitting an NP-hard problem.
I think it’s great for a visualizer like this to encourage people to get used to the power of shell pipelines if possible.
If appropriate, using files as arguments instead of using shell pipelines is a best practice. Commands can optimize for that use case, print better error messages, etc...
And it is not a good thing to encourage useless use of cat. If you goal is to show how your tool is to be used with pipelines, show an actually useful pipeline for example "sed '1b;/abc/!d' file.csv | tv". The "sed" command prints the first line (header), and all lines containing "abc".
It’s very surprising to see a tool that only works as a filter, and doesn’t take file paths as arguments.
tv modifies raw files in the following ways:
1. NA detection and highlighting 2. Printing only significant digits 3. Header and footer meta data
I have been using this a lot at work. There is a lot more work to do, but it is in a usable state.
Give it a try! If you like it then star on Github!