CSV.read() error please provide a valid sink argument

General Usage
,
1

Hello I anm new here. I work through the real great book “Julia Quick syntax reference” from Antonello Lobianco. I typed a code from page 183. What is wrong with

d_table = CSV.read(IOBuffer(“”"
plants new-york chicago topeka
seattle 2.5 1.7 1.8
san-diego 2.5 1.8 1.4
“”“) , delim=” ", ignorerepeated=true, copycols=true)

The error when running is:

ArgumentError: provide a valid sink argument, like using DataFrames; CSV.read(source, DataFrame)

Apparently, it asks for a second argument “DataFrame” ??

Thanks for help
Tony

2

Hi Tony, welcome to the Julia community!
When was the book written?

CSV uses the Tables.jl convention now, which means that it only provides a “backend” for understanding CSVs and the “frontend” needs to be another Tables sink which determines what you get out on the Julia side. It’s really easy, DataFrames is a good default. But this mechanism allows you to read a CSV directly into a database for example, without ever creating an intermediate table.

Furthermore, you should always enclose your code in ` backticks.
So `print(“Hello world!”)` becomes print("Hello world!")

And using tripple ``` makes

```julia
d_table = CSV.read(IOBuffer(“”"
plants new-york chicago topeka
seattle 2.5 1.7 1.8
san-diego 2.5 1.8 1.4
“”“) , delim=” ", ignorerepeated=true, copycols=true)
```

Appear as:

d_table = CSV.read(IOBuffer("""
plants new-york chicago topeka
seattle 2.5 1.7 1.8
san-diego 2.5 1.8 1.4
""") , delim=" ", ignorerepeated=true, copycols=true)

What you asked for is this:

julia>  d_table = CSV.read(IOBuffer("""
        plants new-york chicago topeka
       seattle 2.5 1.7 1.8
       san-diego 2.5 1.8 1.4"""), DataFrame, delim=" ", ignorerepeated=true, copycols=true)
2×4 DataFrame
 Row │ plants     new-york  chicago  topeka
     │ String     Float64   Float64  Float64
─────┼───────────────────────────────────────
   1 │ seattle         2.5      1.7      1.8
   2 │ san-diego       2.5      1.8      1.4
3

Hi FPGro,

Great, thank you. It worked right away. Well, the book is from 2019. Thanks also for your kind advise on how to post code.
Tony

4

Regarding Antonello Lobianco’ s book you may also be interested in checking this out.