How to create strings combining all letters?

Hello.

I’m trying to learn Julia by replicating simple R code in Julia but I’m not even able to create a toy example :anguished:

Let me ask some simple question.

In R there is a function letters, which gives you a vector with all letters or a subset of it, then you don’t need to type them. There is also LETTERS for uppercase.

letters[1:10]
a, b, c, d, e, f, g, h, i, j

How can we get all letters in Julia?

What is the easiest way (and the fastest) to create a vector (or whichever prefered Julia container) with all combinations of letters and/or numbers?
For example

nn <- 3
mynames <- CJ(letters[1:nn], paste0( rep(letters[1:nn],1:nn),
"_20", sprintf("%02d",sequence(1:nn))))[,paste0(V1,V2)]

Here I’m using sprintf in order to be able to run it with longer numbers and get a valid date. And you can use expand.grid instead of CJ but is much slower.

That code produces this vector:

aa_2001, ab_2001, ab_2002, ac_2001, ac_2002, ac_2003, ba_2001, bb_2001, bb_2002, bc_2001, bc_2002, bc_2003, ca_2001, cb_2001, cb_2002, cc_2001, cc_2002, cc_2003

How can I do it with Julia?

Julia’s ranges can act like letters and LETTERS:

julia> collect('a':'j')
10-element Array{Char,1}:
 'a': ASCII/Unicode U+0061 (category Ll: Letter, lowercase)
 'b': ASCII/Unicode U+0062 (category Ll: Letter, lowercase)
 'c': ASCII/Unicode U+0063 (category Ll: Letter, lowercase)
 'd': ASCII/Unicode U+0064 (category Ll: Letter, lowercase)
 'e': ASCII/Unicode U+0065 (category Ll: Letter, lowercase)
 'f': ASCII/Unicode U+0066 (category Ll: Letter, lowercase)
 'g': ASCII/Unicode U+0067 (category Ll: Letter, lowercase)
 'h': ASCII/Unicode U+0068 (category Ll: Letter, lowercase)
 'i': ASCII/Unicode U+0069 (category Ll: Letter, lowercase)
 'j': ASCII/Unicode U+006A (category Ll: Letter, lowercase)

julia> collect('A':'J')
10-element Array{Char,1}:
 'A': ASCII/Unicode U+0041 (category Lu: Letter, uppercase)
 'B': ASCII/Unicode U+0042 (category Lu: Letter, uppercase)
 'C': ASCII/Unicode U+0043 (category Lu: Letter, uppercase)
 'D': ASCII/Unicode U+0044 (category Lu: Letter, uppercase)
 'E': ASCII/Unicode U+0045 (category Lu: Letter, uppercase)
 'F': ASCII/Unicode U+0046 (category Lu: Letter, uppercase)
 'G': ASCII/Unicode U+0047 (category Lu: Letter, uppercase)
 'H': ASCII/Unicode U+0048 (category Lu: Letter, uppercase)
 'I': ASCII/Unicode U+0049 (category Lu: Letter, uppercase)
 'J': ASCII/Unicode U+004A (category Lu: Letter, uppercase)

There are many ways to combine these, one fun way is with broadcasting:

julia> lift(A) = reshape(A, 1, size(A)...)
lift (generic function with 1 method)

julia> lift(A, N) = reshape(A, (1 for _ ∈ 1:N)..., size(A)...)
lift (generic function with 2 methods)

julia> ('a':'c') .* lift('a':'c') .* '_' .* string.(lift(2001:2003, 2))
3×3×3 Array{String,3}:
[:, :, 1] =
 "aa_2001"  "ab_2001"  "ac_2001"
 "ba_2001"  "bb_2001"  "bc_2001"
 "ca_2001"  "cb_2001"  "cc_2001"

[:, :, 2] =
 "aa_2002"  "ab_2002"  "ac_2002"
 "ba_2002"  "bb_2002"  "bc_2002"
 "ca_2002"  "cb_2002"  "cc_2002"

[:, :, 3] =
 "aa_2003"  "ab_2003"  "ac_2003"
 "ba_2003"  "bb_2003"  "bc_2003"
 "ca_2003"  "cb_2003"  "cc_2003"
4 Likes

You can also use Iterators.product

julia> [join(x, "_") for x in Iterators.product(["a", "b"], ["x", "y"], ["2001", "2002", "2003"])]
4 Likes

Would it be easier or more efficient using this library?

i don’t know. The current solution seems pretty good. Plus if you are trying to learn Julia for the first time it’s probably better to become familiar with the Base functions.

1 Like

What I want not just [“a”, “b”] but all letters from “a” to “z”?

Then do that?

julia> ('a':'z') .* lift('a':'z') .* '_' .* string.(lift(2001:2003, 2))
26×26×3 Array{String,3}:
[:, :, 1] =
 "aa_2001"  "ab_2001"  "ac_2001"  "ad_2001"  …  "aw_2001"  "ax_2001"  "ay_2001"  "az_2001"
 "ba_2001"  "bb_2001"  "bc_2001"  "bd_2001"     "bw_2001"  "bx_2001"  "by_2001"  "bz_2001"
 "ca_2001"  "cb_2001"  "cc_2001"  "cd_2001"     "cw_2001"  "cx_2001"  "cy_2001"  "cz_2001"
 "da_2001"  "db_2001"  "dc_2001"  "dd_2001"     "dw_2001"  "dx_2001"  "dy_2001"  "dz_2001"
 "ea_2001"  "eb_2001"  "ec_2001"  "ed_2001"     "ew_2001"  "ex_2001"  "ey_2001"  "ez_2001"
 "fa_2001"  "fb_2001"  "fc_2001"  "fd_2001"  …  "fw_2001"  "fx_2001"  "fy_2001"  "fz_2001"
 "ga_2001"  "gb_2001"  "gc_2001"  "gd_2001"     "gw_2001"  "gx_2001"  "gy_2001"  "gz_2001"
 "ha_2001"  "hb_2001"  "hc_2001"  "hd_2001"     "hw_2001"  "hx_2001"  "hy_2001"  "hz_2001"
 "ia_2001"  "ib_2001"  "ic_2001"  "id_2001"     "iw_2001"  "ix_2001"  "iy_2001"  "iz_2001"
 "ja_2001"  "jb_2001"  "jc_2001"  "jd_2001"     "jw_2001"  "jx_2001"  "jy_2001"  "jz_2001"
 "ka_2001"  "kb_2001"  "kc_2001"  "kd_2001"  …  "kw_2001"  "kx_2001"  "ky_2001"  "kz_2001"
 "la_2001"  "lb_2001"  "lc_2001"  "ld_2001"     "lw_2001"  "lx_2001"  "ly_2001"  "lz_2001"
 "ma_2001"  "mb_2001"  "mc_2001"  "md_2001"     "mw_2001"  "mx_2001"  "my_2001"  "mz_2001"
 "na_2001"  "nb_2001"  "nc_2001"  "nd_2001"     "nw_2001"  "nx_2001"  "ny_2001"  "nz_2001"
 "oa_2001"  "ob_2001"  "oc_2001"  "od_2001"     "ow_2001"  "ox_2001"  "oy_2001"  "oz_2001"
 "pa_2001"  "pb_2001"  "pc_2001"  "pd_2001"  …  "pw_2001"  "px_2001"  "py_2001"  "pz_2001"
 "qa_2001"  "qb_2001"  "qc_2001"  "qd_2001"     "qw_2001"  "qx_2001"  "qy_2001"  "qz_2001"
 "ra_2001"  "rb_2001"  "rc_2001"  "rd_2001"     "rw_2001"  "rx_2001"  "ry_2001"  "rz_2001"
 "sa_2001"  "sb_2001"  "sc_2001"  "sd_2001"     "sw_2001"  "sx_2001"  "sy_2001"  "sz_2001"
 "ta_2001"  "tb_2001"  "tc_2001"  "td_2001"     "tw_2001"  "tx_2001"  "ty_2001"  "tz_2001"
 "ua_2001"  "ub_2001"  "uc_2001"  "ud_2001"  …  "uw_2001"  "ux_2001"  "uy_2001"  "uz_2001"
 "va_2001"  "vb_2001"  "vc_2001"  "vd_2001"     "vw_2001"  "vx_2001"  "vy_2001"  "vz_2001"
 "wa_2001"  "wb_2001"  "wc_2001"  "wd_2001"     "ww_2001"  "wx_2001"  "wy_2001"  "wz_2001"
 "xa_2001"  "xb_2001"  "xc_2001"  "xd_2001"     "xw_2001"  "xx_2001"  "xy_2001"  "xz_2001"
 "ya_2001"  "yb_2001"  "yc_2001"  "yd_2001"     "yw_2001"  "yx_2001"  "yy_2001"  "yz_2001"
 "za_2001"  "zb_2001"  "zc_2001"  "zd_2001"  …  "zw_2001"  "zx_2001"  "zy_2001"  "zz_2001"

[:, :, 2] =
 "aa_2002"  "ab_2002"  "ac_2002"  "ad_2002"  …  "aw_2002"  "ax_2002"  "ay_2002"  "az_2002"
 "ba_2002"  "bb_2002"  "bc_2002"  "bd_2002"     "bw_2002"  "bx_2002"  "by_2002"  "bz_2002"
 "ca_2002"  "cb_2002"  "cc_2002"  "cd_2002"     "cw_2002"  "cx_2002"  "cy_2002"  "cz_2002"
 "da_2002"  "db_2002"  "dc_2002"  "dd_2002"     "dw_2002"  "dx_2002"  "dy_2002"  "dz_2002"
 "ea_2002"  "eb_2002"  "ec_2002"  "ed_2002"     "ew_2002"  "ex_2002"  "ey_2002"  "ez_2002"
 "fa_2002"  "fb_2002"  "fc_2002"  "fd_2002"  …  "fw_2002"  "fx_2002"  "fy_2002"  "fz_2002"
 "ga_2002"  "gb_2002"  "gc_2002"  "gd_2002"     "gw_2002"  "gx_2002"  "gy_2002"  "gz_2002"
 "ha_2002"  "hb_2002"  "hc_2002"  "hd_2002"     "hw_2002"  "hx_2002"  "hy_2002"  "hz_2002"
 "ia_2002"  "ib_2002"  "ic_2002"  "id_2002"     "iw_2002"  "ix_2002"  "iy_2002"  "iz_2002"
 "ja_2002"  "jb_2002"  "jc_2002"  "jd_2002"     "jw_2002"  "jx_2002"  "jy_2002"  "jz_2002"
 "ka_2002"  "kb_2002"  "kc_2002"  "kd_2002"  …  "kw_2002"  "kx_2002"  "ky_2002"  "kz_2002"
 "la_2002"  "lb_2002"  "lc_2002"  "ld_2002"     "lw_2002"  "lx_2002"  "ly_2002"  "lz_2002"
 "ma_2002"  "mb_2002"  "mc_2002"  "md_2002"     "mw_2002"  "mx_2002"  "my_2002"  "mz_2002"
 "na_2002"  "nb_2002"  "nc_2002"  "nd_2002"     "nw_2002"  "nx_2002"  "ny_2002"  "nz_2002"
 "oa_2002"  "ob_2002"  "oc_2002"  "od_2002"     "ow_2002"  "ox_2002"  "oy_2002"  "oz_2002"
 "pa_2002"  "pb_2002"  "pc_2002"  "pd_2002"  …  "pw_2002"  "px_2002"  "py_2002"  "pz_2002"
 "qa_2002"  "qb_2002"  "qc_2002"  "qd_2002"     "qw_2002"  "qx_2002"  "qy_2002"  "qz_2002"
 "ra_2002"  "rb_2002"  "rc_2002"  "rd_2002"     "rw_2002"  "rx_2002"  "ry_2002"  "rz_2002"
 "sa_2002"  "sb_2002"  "sc_2002"  "sd_2002"     "sw_2002"  "sx_2002"  "sy_2002"  "sz_2002"
 "ta_2002"  "tb_2002"  "tc_2002"  "td_2002"     "tw_2002"  "tx_2002"  "ty_2002"  "tz_2002"
 "ua_2002"  "ub_2002"  "uc_2002"  "ud_2002"  …  "uw_2002"  "ux_2002"  "uy_2002"  "uz_2002"
 "va_2002"  "vb_2002"  "vc_2002"  "vd_2002"     "vw_2002"  "vx_2002"  "vy_2002"  "vz_2002"
 "wa_2002"  "wb_2002"  "wc_2002"  "wd_2002"     "ww_2002"  "wx_2002"  "wy_2002"  "wz_2002"
 "xa_2002"  "xb_2002"  "xc_2002"  "xd_2002"     "xw_2002"  "xx_2002"  "xy_2002"  "xz_2002"
 "ya_2002"  "yb_2002"  "yc_2002"  "yd_2002"     "yw_2002"  "yx_2002"  "yy_2002"  "yz_2002"
 "za_2002"  "zb_2002"  "zc_2002"  "zd_2002"  …  "zw_2002"  "zx_2002"  "zy_2002"  "zz_2002"

[:, :, 3] =
 "aa_2003"  "ab_2003"  "ac_2003"  "ad_2003"  …  "aw_2003"  "ax_2003"  "ay_2003"  "az_2003"
 "ba_2003"  "bb_2003"  "bc_2003"  "bd_2003"     "bw_2003"  "bx_2003"  "by_2003"  "bz_2003"
 "ca_2003"  "cb_2003"  "cc_2003"  "cd_2003"     "cw_2003"  "cx_2003"  "cy_2003"  "cz_2003"
 "da_2003"  "db_2003"  "dc_2003"  "dd_2003"     "dw_2003"  "dx_2003"  "dy_2003"  "dz_2003"
 "ea_2003"  "eb_2003"  "ec_2003"  "ed_2003"     "ew_2003"  "ex_2003"  "ey_2003"  "ez_2003"
 "fa_2003"  "fb_2003"  "fc_2003"  "fd_2003"  …  "fw_2003"  "fx_2003"  "fy_2003"  "fz_2003"
 "ga_2003"  "gb_2003"  "gc_2003"  "gd_2003"     "gw_2003"  "gx_2003"  "gy_2003"  "gz_2003"
 "ha_2003"  "hb_2003"  "hc_2003"  "hd_2003"     "hw_2003"  "hx_2003"  "hy_2003"  "hz_2003"
 "ia_2003"  "ib_2003"  "ic_2003"  "id_2003"     "iw_2003"  "ix_2003"  "iy_2003"  "iz_2003"
 "ja_2003"  "jb_2003"  "jc_2003"  "jd_2003"     "jw_2003"  "jx_2003"  "jy_2003"  "jz_2003"
 "ka_2003"  "kb_2003"  "kc_2003"  "kd_2003"  …  "kw_2003"  "kx_2003"  "ky_2003"  "kz_2003"
 "la_2003"  "lb_2003"  "lc_2003"  "ld_2003"     "lw_2003"  "lx_2003"  "ly_2003"  "lz_2003"
 "ma_2003"  "mb_2003"  "mc_2003"  "md_2003"     "mw_2003"  "mx_2003"  "my_2003"  "mz_2003"
 "na_2003"  "nb_2003"  "nc_2003"  "nd_2003"     "nw_2003"  "nx_2003"  "ny_2003"  "nz_2003"
 "oa_2003"  "ob_2003"  "oc_2003"  "od_2003"     "ow_2003"  "ox_2003"  "oy_2003"  "oz_2003"
 "pa_2003"  "pb_2003"  "pc_2003"  "pd_2003"  …  "pw_2003"  "px_2003"  "py_2003"  "pz_2003"
 "qa_2003"  "qb_2003"  "qc_2003"  "qd_2003"     "qw_2003"  "qx_2003"  "qy_2003"  "qz_2003"
 "ra_2003"  "rb_2003"  "rc_2003"  "rd_2003"     "rw_2003"  "rx_2003"  "ry_2003"  "rz_2003"
 "sa_2003"  "sb_2003"  "sc_2003"  "sd_2003"     "sw_2003"  "sx_2003"  "sy_2003"  "sz_2003"
 "ta_2003"  "tb_2003"  "tc_2003"  "td_2003"     "tw_2003"  "tx_2003"  "ty_2003"  "tz_2003"
 "ua_2003"  "ub_2003"  "uc_2003"  "ud_2003"  …  "uw_2003"  "ux_2003"  "uy_2003"  "uz_2003"
 "va_2003"  "vb_2003"  "vc_2003"  "vd_2003"     "vw_2003"  "vx_2003"  "vy_2003"  "vz_2003"
 "wa_2003"  "wb_2003"  "wc_2003"  "wd_2003"     "ww_2003"  "wx_2003"  "wy_2003"  "wz_2003"
 "xa_2003"  "xb_2003"  "xc_2003"  "xd_2003"     "xw_2003"  "xx_2003"  "xy_2003"  "xz_2003"
 "ya_2003"  "yb_2003"  "yc_2003"  "yd_2003"     "yw_2003"  "yx_2003"  "yy_2003"  "yz_2003"
 "za_2003"  "zb_2003"  "zc_2003"  "zd_2003"  …  "zw_2003"  "zx_2003"  "zy_2003"  "zz_2003"

Or with @pdeffebach’s method:

julia> map(Iterators.product('a':'z', 'a':'z', string.(2001:2003))) do (x, y, z)
           x*y*'_'*z
       end
26×26×3 Array{String,3}:
[:, :, 1] =
 "aa_2001"  "ab_2001"  "ac_2001"  "ad_2001"  …  "aw_2001"  "ax_2001"  "ay_2001"  "az_2001"
 "ba_2001"  "bb_2001"  "bc_2001"  "bd_2001"     "bw_2001"  "bx_2001"  "by_2001"  "bz_2001"
 "ca_2001"  "cb_2001"  "cc_2001"  "cd_2001"     "cw_2001"  "cx_2001"  "cy_2001"  "cz_2001"
 "da_2001"  "db_2001"  "dc_2001"  "dd_2001"     "dw_2001"  "dx_2001"  "dy_2001"  "dz_2001"
 "ea_2001"  "eb_2001"  "ec_2001"  "ed_2001"     "ew_2001"  "ex_2001"  "ey_2001"  "ez_2001"
 "fa_2001"  "fb_2001"  "fc_2001"  "fd_2001"  …  "fw_2001"  "fx_2001"  "fy_2001"  "fz_2001"
 "ga_2001"  "gb_2001"  "gc_2001"  "gd_2001"     "gw_2001"  "gx_2001"  "gy_2001"  "gz_2001"
 "ha_2001"  "hb_2001"  "hc_2001"  "hd_2001"     "hw_2001"  "hx_2001"  "hy_2001"  "hz_2001"
 "ia_2001"  "ib_2001"  "ic_2001"  "id_2001"     "iw_2001"  "ix_2001"  "iy_2001"  "iz_2001"
 "ja_2001"  "jb_2001"  "jc_2001"  "jd_2001"     "jw_2001"  "jx_2001"  "jy_2001"  "jz_2001"
 "ka_2001"  "kb_2001"  "kc_2001"  "kd_2001"  …  "kw_2001"  "kx_2001"  "ky_2001"  "kz_2001"
 "la_2001"  "lb_2001"  "lc_2001"  "ld_2001"     "lw_2001"  "lx_2001"  "ly_2001"  "lz_2001"
 "ma_2001"  "mb_2001"  "mc_2001"  "md_2001"     "mw_2001"  "mx_2001"  "my_2001"  "mz_2001"
 "na_2001"  "nb_2001"  "nc_2001"  "nd_2001"     "nw_2001"  "nx_2001"  "ny_2001"  "nz_2001"
 "oa_2001"  "ob_2001"  "oc_2001"  "od_2001"     "ow_2001"  "ox_2001"  "oy_2001"  "oz_2001"
 "pa_2001"  "pb_2001"  "pc_2001"  "pd_2001"  …  "pw_2001"  "px_2001"  "py_2001"  "pz_2001"
 "qa_2001"  "qb_2001"  "qc_2001"  "qd_2001"     "qw_2001"  "qx_2001"  "qy_2001"  "qz_2001"
 "ra_2001"  "rb_2001"  "rc_2001"  "rd_2001"     "rw_2001"  "rx_2001"  "ry_2001"  "rz_2001"
 "sa_2001"  "sb_2001"  "sc_2001"  "sd_2001"     "sw_2001"  "sx_2001"  "sy_2001"  "sz_2001"
 "ta_2001"  "tb_2001"  "tc_2001"  "td_2001"     "tw_2001"  "tx_2001"  "ty_2001"  "tz_2001"
 "ua_2001"  "ub_2001"  "uc_2001"  "ud_2001"  …  "uw_2001"  "ux_2001"  "uy_2001"  "uz_2001"
 "va_2001"  "vb_2001"  "vc_2001"  "vd_2001"     "vw_2001"  "vx_2001"  "vy_2001"  "vz_2001"
 "wa_2001"  "wb_2001"  "wc_2001"  "wd_2001"     "ww_2001"  "wx_2001"  "wy_2001"  "wz_2001"
 "xa_2001"  "xb_2001"  "xc_2001"  "xd_2001"     "xw_2001"  "xx_2001"  "xy_2001"  "xz_2001"
 "ya_2001"  "yb_2001"  "yc_2001"  "yd_2001"     "yw_2001"  "yx_2001"  "yy_2001"  "yz_2001"
 "za_2001"  "zb_2001"  "zc_2001"  "zd_2001"  …  "zw_2001"  "zx_2001"  "zy_2001"  "zz_2001"

[:, :, 2] =
 "aa_2002"  "ab_2002"  "ac_2002"  "ad_2002"  …  "aw_2002"  "ax_2002"  "ay_2002"  "az_2002"
 "ba_2002"  "bb_2002"  "bc_2002"  "bd_2002"     "bw_2002"  "bx_2002"  "by_2002"  "bz_2002"
 "ca_2002"  "cb_2002"  "cc_2002"  "cd_2002"     "cw_2002"  "cx_2002"  "cy_2002"  "cz_2002"
 "da_2002"  "db_2002"  "dc_2002"  "dd_2002"     "dw_2002"  "dx_2002"  "dy_2002"  "dz_2002"
 "ea_2002"  "eb_2002"  "ec_2002"  "ed_2002"     "ew_2002"  "ex_2002"  "ey_2002"  "ez_2002"
 "fa_2002"  "fb_2002"  "fc_2002"  "fd_2002"  …  "fw_2002"  "fx_2002"  "fy_2002"  "fz_2002"
 "ga_2002"  "gb_2002"  "gc_2002"  "gd_2002"     "gw_2002"  "gx_2002"  "gy_2002"  "gz_2002"
 "ha_2002"  "hb_2002"  "hc_2002"  "hd_2002"     "hw_2002"  "hx_2002"  "hy_2002"  "hz_2002"
 "ia_2002"  "ib_2002"  "ic_2002"  "id_2002"     "iw_2002"  "ix_2002"  "iy_2002"  "iz_2002"
 "ja_2002"  "jb_2002"  "jc_2002"  "jd_2002"     "jw_2002"  "jx_2002"  "jy_2002"  "jz_2002"
 "ka_2002"  "kb_2002"  "kc_2002"  "kd_2002"  …  "kw_2002"  "kx_2002"  "ky_2002"  "kz_2002"
 "la_2002"  "lb_2002"  "lc_2002"  "ld_2002"     "lw_2002"  "lx_2002"  "ly_2002"  "lz_2002"
 "ma_2002"  "mb_2002"  "mc_2002"  "md_2002"     "mw_2002"  "mx_2002"  "my_2002"  "mz_2002"
 "na_2002"  "nb_2002"  "nc_2002"  "nd_2002"     "nw_2002"  "nx_2002"  "ny_2002"  "nz_2002"
 "oa_2002"  "ob_2002"  "oc_2002"  "od_2002"     "ow_2002"  "ox_2002"  "oy_2002"  "oz_2002"
 "pa_2002"  "pb_2002"  "pc_2002"  "pd_2002"  …  "pw_2002"  "px_2002"  "py_2002"  "pz_2002"
 "qa_2002"  "qb_2002"  "qc_2002"  "qd_2002"     "qw_2002"  "qx_2002"  "qy_2002"  "qz_2002"
 "ra_2002"  "rb_2002"  "rc_2002"  "rd_2002"     "rw_2002"  "rx_2002"  "ry_2002"  "rz_2002"
 "sa_2002"  "sb_2002"  "sc_2002"  "sd_2002"     "sw_2002"  "sx_2002"  "sy_2002"  "sz_2002"
 "ta_2002"  "tb_2002"  "tc_2002"  "td_2002"     "tw_2002"  "tx_2002"  "ty_2002"  "tz_2002"
 "ua_2002"  "ub_2002"  "uc_2002"  "ud_2002"  …  "uw_2002"  "ux_2002"  "uy_2002"  "uz_2002"
 "va_2002"  "vb_2002"  "vc_2002"  "vd_2002"     "vw_2002"  "vx_2002"  "vy_2002"  "vz_2002"
 "wa_2002"  "wb_2002"  "wc_2002"  "wd_2002"     "ww_2002"  "wx_2002"  "wy_2002"  "wz_2002"
 "xa_2002"  "xb_2002"  "xc_2002"  "xd_2002"     "xw_2002"  "xx_2002"  "xy_2002"  "xz_2002"
 "ya_2002"  "yb_2002"  "yc_2002"  "yd_2002"     "yw_2002"  "yx_2002"  "yy_2002"  "yz_2002"
 "za_2002"  "zb_2002"  "zc_2002"  "zd_2002"  …  "zw_2002"  "zx_2002"  "zy_2002"  "zz_2002"

[:, :, 3] =
 "aa_2003"  "ab_2003"  "ac_2003"  "ad_2003"  …  "aw_2003"  "ax_2003"  "ay_2003"  "az_2003"
 "ba_2003"  "bb_2003"  "bc_2003"  "bd_2003"     "bw_2003"  "bx_2003"  "by_2003"  "bz_2003"
 "ca_2003"  "cb_2003"  "cc_2003"  "cd_2003"     "cw_2003"  "cx_2003"  "cy_2003"  "cz_2003"
 "da_2003"  "db_2003"  "dc_2003"  "dd_2003"     "dw_2003"  "dx_2003"  "dy_2003"  "dz_2003"
 "ea_2003"  "eb_2003"  "ec_2003"  "ed_2003"     "ew_2003"  "ex_2003"  "ey_2003"  "ez_2003"
 "fa_2003"  "fb_2003"  "fc_2003"  "fd_2003"  …  "fw_2003"  "fx_2003"  "fy_2003"  "fz_2003"
 "ga_2003"  "gb_2003"  "gc_2003"  "gd_2003"     "gw_2003"  "gx_2003"  "gy_2003"  "gz_2003"
 "ha_2003"  "hb_2003"  "hc_2003"  "hd_2003"     "hw_2003"  "hx_2003"  "hy_2003"  "hz_2003"
 "ia_2003"  "ib_2003"  "ic_2003"  "id_2003"     "iw_2003"  "ix_2003"  "iy_2003"  "iz_2003"
 "ja_2003"  "jb_2003"  "jc_2003"  "jd_2003"     "jw_2003"  "jx_2003"  "jy_2003"  "jz_2003"
 "ka_2003"  "kb_2003"  "kc_2003"  "kd_2003"  …  "kw_2003"  "kx_2003"  "ky_2003"  "kz_2003"
 "la_2003"  "lb_2003"  "lc_2003"  "ld_2003"     "lw_2003"  "lx_2003"  "ly_2003"  "lz_2003"
 "ma_2003"  "mb_2003"  "mc_2003"  "md_2003"     "mw_2003"  "mx_2003"  "my_2003"  "mz_2003"
 "na_2003"  "nb_2003"  "nc_2003"  "nd_2003"     "nw_2003"  "nx_2003"  "ny_2003"  "nz_2003"
 "oa_2003"  "ob_2003"  "oc_2003"  "od_2003"     "ow_2003"  "ox_2003"  "oy_2003"  "oz_2003"
 "pa_2003"  "pb_2003"  "pc_2003"  "pd_2003"  …  "pw_2003"  "px_2003"  "py_2003"  "pz_2003"
 "qa_2003"  "qb_2003"  "qc_2003"  "qd_2003"     "qw_2003"  "qx_2003"  "qy_2003"  "qz_2003"
 "ra_2003"  "rb_2003"  "rc_2003"  "rd_2003"     "rw_2003"  "rx_2003"  "ry_2003"  "rz_2003"
 "sa_2003"  "sb_2003"  "sc_2003"  "sd_2003"     "sw_2003"  "sx_2003"  "sy_2003"  "sz_2003"
 "ta_2003"  "tb_2003"  "tc_2003"  "td_2003"     "tw_2003"  "tx_2003"  "ty_2003"  "tz_2003"
 "ua_2003"  "ub_2003"  "uc_2003"  "ud_2003"  …  "uw_2003"  "ux_2003"  "uy_2003"  "uz_2003"
 "va_2003"  "vb_2003"  "vc_2003"  "vd_2003"     "vw_2003"  "vx_2003"  "vy_2003"  "vz_2003"
 "wa_2003"  "wb_2003"  "wc_2003"  "wd_2003"     "ww_2003"  "wx_2003"  "wy_2003"  "wz_2003"
 "xa_2003"  "xb_2003"  "xc_2003"  "xd_2003"     "xw_2003"  "xx_2003"  "xy_2003"  "xz_2003"
 "ya_2003"  "yb_2003"  "yc_2003"  "yd_2003"     "yw_2003"  "yx_2003"  "yy_2003"  "yz_2003"
 "za_2003"  "zb_2003"  "zc_2003"  "zd_2003"  …  "zw_2003"  "zx_2003"  "zy_2003"  "zz_2003"
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