--- Implements a concept that stores a collection of parameter groups.
--- The class for stroing a collection of parameter groups (`nerv.Param`).
local ParamRepo = nerv.class("nerv.ParamRepo")
--- The location constants for `loc_type`.
-- @field ON_DEVICE the storage is on device (GPU RAM)
-- @field ON_HOST the storage is on host (main RAM)
ParamRepo.LOC_TYPES = {
ON_DEVICE = {},
ON_HOST = {}
}
--- The constructor.
-- @param plist an array of parameters that will be initially in the collection
-- @param loc_type the type of storage location, see `nerv.ParamRepo.LOC_TYPES`
function ParamRepo:__init(plist, loc_type)
self.params = {}
self.loc_type = loc_type or ParamRepo.LOC_TYPES.ON_HOST
local function make_checker(tname)
return function (mat)
if not nerv.is_type(mat, tname) then
nerv.error("unexpected param type in repo specification")
end
end
end
self.make_copier = function (mat_type, copy_method)
return function (mat)
local target = mat_type(mat:nrow(), mat:ncol())
mat[copy_method](mat, target)
return target
end
end
if self.loc_type == ParamRepo.LOC_TYPES.ON_HOST then
self.checker = make_checker("nerv.MMatrix")
else
self.checker = make_checker("nerv.CuMatrix")
end
if plist ~= nil then
for i, p in ipairs(plist) do
p:check(self.checker)
self.params[p.id] = p
end
end
end
--- Add a parameter to the collection.
-- @param p the parameter to be added
function ParamRepo:add(p)
if self.params[p.id] ~= nil then
nerv.error("duplicate params with the same id: %s", p.id)
end
p:check(self.checker)
self.params[p.id] = p
end
--- Remove a parameter from the collection.
-- @param pid the id of the parameter to be removed
function ParamRepo:remove(pid)
if self.params[pid] == nil then
nerv.error("param %s does not exit", pid)
end
self.params[pid] = nil
end
--- Merge two or more parameter collecitons.
-- @param repos an array of parameter repos to be merged
-- @param loc_type the type of storage location, see `nerv.ParamRepo.LOC_TYPES`
-- @return the merged parameter collection (repo)
function ParamRepo.merge(repos, loc_type)
-- TODO: remove redundant `loc_type` and check the consistency of `loc_type`
-- from different merging param repos.
local self = nerv.ParamRepo(nil, loc_type)
for i, repo in ipairs(repos) do
if not nerv.is_type(repo, "nerv.ParamRepo") then
nerv.error("nerv.ParamRepo objects expected, got %s", repo)
end
for pid, p in pairs(repo.params) do
self:add(p)
end
end
return self
end
--- Import parameters from a NERV chunk file.
-- @param param_files an array of filenames of the files to be loaded from
-- @param gconf a table describing the computation state and providing
-- with some global settings
-- @param pids optional, an array of identifiers of the parameters to be imported
function ParamRepo:import(param_files, gconf, pids)
if type(param_files) ~= "table" then
nerv.error("param file table is need")
end
for i = 1, #param_files do
local pf = nerv.ChunkFile(param_files[i], "r")
for cid, cspec in pairs(pf.metadata) do
if pids == nil or pids[cid] ~= nil then
local p = pf:read_chunk(cid, gconf)
if not nerv.is_type(p, "nerv.Param") then
nerv.error("param chunk is expected")
end
self:add(p)
end
end
end
end
--- Export the parameter collection to a NERV chunk file.
-- @param param_file the output filename
-- @param pids optional, the identifiers of the parameters to be exported
function ParamRepo:export(param_file, pids)
cf = nerv.ChunkFile(param_file, "w")
if pids == nil then
for id, p in pairs(self.params) do
cf:write_chunk(p)
end
else
for i, pid in ipairs(pids) do
cf:write_chunk(self:get_param(pid))
end
end
cf:close()
end
--- Test whether the collection has a parameter.
-- @param pid the identifier to be tested
-- @return true if a parameter with the identifier exists
function ParamRepo:has_param(pid)
return self.params[pid] ~= nil
end
--- Retrieve the parameter by the identifier.
-- @param pid the identifier of the parameter to be retrieved
-- @return the retrieved parameter
function ParamRepo:get_param(pid)
local p = self.params[pid]
if p == nil then
nerv.error("param with id %s not found", pid)
end
return p
end
--- Create a copy of the current collection.
-- @param loc_type the storage location of the new copy
-- @param gconf a table describing the computation state and providing
-- with some global settings
-- @param pids optional, an array of identifiers of the parameters to be copied
function ParamRepo:copy(loc_type, gconf, pids)
local copier
local target = nerv.ParamRepo(nil, loc_type)
if loc_type == nil then
loc_type = self.loc_type
end
if loc_type == ParamRepo.LOC_TYPES.ON_HOST then
copier = self.make_copier(gconf.mmat_type, 'copy_toh')
else
copier = self.make_copier(gconf.cumat_type, 'copy_tod')
end
if pids == nil then
for id, p in pairs(self.params) do
target.params[id] = p:copy(copier)
end
else
for i, pid in ipairs(pids) do
target.params[pid] = self:get_param(pid):copy(copier)
end
end
return target
end