how to sum string type load from csv? and how to convert string column to timestamp?

[xkungfu]

my csv file column fields: date, username, vol, type

all fields are string fromat.

can't load as double, but when load as string,

I can't sum vol column, and can't select rows by date range.

how to convert string column to int or double?

and how to convert string column to timestamp?

PS: why I can't find any doc and issue about my question? why others didn't have this issue?

thanks!

[xkungfu]

I try to convert string to int by below code: auto vol = xt::col(csvdata, 2); auto vol_int = xt::cast(vol);

it can't work too!

[xkungfu]

any good man can help?

and now I find xt::cast need xt::xarray as param. but xt::col is xt::view.

then, how to convert xt::view to xt::xarray? or how to get c col from csv to xt::xarray?

it is a maze without exits for me .

[xkungfu]

thanks!