Implement preliminary GDT linear model function - gsl-shell.git - gsl-shell

diff --git a/gdt-plot.lua b/gdt-plot.lua
index a1308c4d..8d624474 100644
--- a/gdt-plot.lua
+++ b/gdt-plot.lua

@@ -1,4 +1,5 @@

local concat = table.concat

+local select = select

local function collate(ls)

return concat(ls, ' ')

@@ -257,7 +258,41 @@ local function gdt_table_reduce(t_src, jxs, jys, jes)

return t

end

+local function count_args(...)

+ return select('#', ...)

+end

+

+local function set_elements(X, P, i, ...)

+ for k = 1, P do

+ local v = select(k, ...)

+ X:set(i, k, v)

+ end

+end

+

+local function gdt_table_linfit(t, f, jy)

+ local N, M = t:dim()

+ local name = {}

+ for k = 1, M do

+ name[k] = t:get_header(k)

+ end

+ local row = {}

+ for k = 1, M do

+ row[name[k]] = t:get(1, k)

+ end

+ local P = count_args(f(row))

+

+ local X, Y = matrix.alloc(N, P), matrix.alloc(N, 1)

+ for i = 1, N do

+ for k = 1, M do row[name[k]] = t:get(i, k) end

+ set_elements(X, P, i, f(row))

+ Y:set(i, 1, t:get(i, jy))

+ end

+

+ return num.linfit(X, Y)

+end

+

gdt.barplot = gdt_table_barplot

gdt.plot = gdt_table_lineplot

gdt.xyplot = gdt_table_xyplot

gdt.reduce = gdt_table_reduce

+gdt.lm = gdt_table_linfit