Find subcategories of the given overall SIC industry code(s)
Source:R/sic_xyz.R
      sic_subcodes_from_code.RdGiven 3-digit SIC code, for example, get all SIC that start with those digits.
Arguments
- mycodes
 SIC codes vector, of 2 to 4 digits each. See https://siccode.com
Value
a subset of the sictable data.table (not just the codes column)
Details
similar idea was naics2children() but this is more robust
See sic_from_any() which uses this
See also
sic_subcodes_from_code() sic_from_code()  sic_from_name()  sic_from_any()
Examples
  # codes starting with '07'
  sic_subcodes_from_code('07')
#>      code     n2     n3     n4                                 name
#>    <char> <char> <char> <char>                               <char>
#> 1:   0700     07    070   0700                Agricultural services
#> 2:   0710     07    071   0710            Soil preparation services
#> 3:   0720     07    072   0720                        Crop services
#> 4:   0740     07    074   0740                  Veterinary services
#> 5:   0750     07    075   0750   Animal services, except veterinary
#> 6:   0760     07    076   0760   Farm labor and management services
#> 7:   0761     07    076   0761               Farm labor contractors
#> 8:   0762     07    076   0762             Farm management services
#> 9:   0780     07    078   0780 Landscape and horticultural services
#>                                       num_name
#>                                         <char>
#> 1:                0700 - Agricultural services
#> 2:            0710 - Soil preparation services
#> 3:                        0720 - Crop services
#> 4:                  0740 - Veterinary services
#> 5:   0750 - Animal services, except veterinary
#> 6:   0760 - Farm labor and management services
#> 7:               0761 - Farm labor contractors
#> 8:             0762 - Farm management services
#> 9: 0780 - Landscape and horticultural services
  # codes starting with '078'
  sic_subcodes_from_code('078')
#>      code     n2     n3     n4                                 name
#>    <char> <char> <char> <char>                               <char>
#> 1:   0780     07    078   0780 Landscape and horticultural services
#>                                       num_name
#>                                         <char>
#> 1: 0780 - Landscape and horticultural services