fix bug & add stop option

sample.lua

@@ -28,7 +28,8 @@ cmd:argument('-model','model checkpoint to use for sampling')
 cmd:option('-seed',123,'random number generator\'s seed')
 cmd:option('-sample',1,' 0 to use max at each timestep, 1 to sample at each timestep')
 cmd:option('-primetext',"",'used as a prompt to "seed" the state of the LSTM using a given sequence, before we sample.')
-cmd:option('-length',2000,'number of characters to sample')
+cmd:option('-length',2000,'max number of characters to sample')
+cmd:option('-stop','\\n\\n\\n\\n\\n','stop sampling when detected')
 cmd:option('-temperature',1,'temperature of sampling')
 cmd:option('-gpuid',0,'which gpu to use. -1 = use CPU')
 cmd:option('-verbose',1,'set to 0 to ONLY print the sampled text, no diagnostics')
@@ -137,22 +138,24 @@ else
 end
 
 -- start sampling/argmaxing
+result = ''
 for i=1, opt.length do
 
     -- log probabilities from the previous timestep
 	-- make sure the output char is not UNKNOW
-	prev_char = 'UNKNOW'
-	while(prev_char == 'UNKNOW') do
-		if opt.sample == 0 then
-			-- use argmax
-			local _, prev_char_ = prediction:max(2)
-			prev_char = prev_char_:resize(1)
-		else
-			-- use sampling
+	if opt.sample == 0 then
+		-- use argmax
+		local _, prev_char_ = prediction:max(2)
+		prev_char = prev_char_:resize(1)
+	else
+		-- use sampling
+		real_char = 'UNKNOW'
+		while(real_char == 'UNKNOW') do
 			prediction:div(opt.temperature) -- scale by temperature
 			local probs = torch.exp(prediction):squeeze()
 			probs:div(torch.sum(probs)) -- renormalize so probs sum to one
 			prev_char = torch.multinomial(probs:float(), 1):resize(1):float()
+			real_char = ivocab[prev_char[1]]
 		end
 	end
 
@@ -162,7 +165,13 @@ for i=1, opt.length do
     for i=1,state_size do table.insert(current_state, lst[i]) end
     prediction = lst[#lst] -- last element holds the log probabilities
 
-    io.write(ivocab[prev_char[1]])
+    -- io.write(ivocab[prev_char[1]])
+    result = result .. ivocab[prev_char[1]]
+
+	-- in my data, five \n represent the end of each document
+	-- so count \n to stop sampling
+    if string.find(result, opt.stop) then break end
 end
+io.write(result)
 io.write('\n') io.flush()