How to properly nest exp.addData when looping over blocks and trials

Coding
1

I just added a loop to my code so that my trials are broken up into ‘blocks’ (not a blocked design, really just for the sake of giving participants a break every few minutes), and it has done something funky to my log saves. As I have it now, my script is only logging information about the last trial in the loop. I saw a thread with a similar issue, but they were only iterating through trials, not blocks and trials, and I’m not quite sure how to interpret the answer given there to my code.

# Iterate through conditions
for block_id in block_order:
	block_content = trials[trials.blockID==block_id]
	block_content = shuffle(block_content)
	blockNum += 1
	prompt = 'This is block %s out of %s.\n\nPlease use this time to blink, stretch, adjust yourself. Remember to hold still and try not to blink when you advance to the next block. \n\nPress any button to continue.'%(str(blockNum), n_blocks)
	present_text(prompt)

	for _, trial in block_content.iterrows():

		correct_answer = random.randint(1, 2) == 1

	# Present Fixation: On time: 300ms Off time: 300ms
		present_fixation()

	# Present Stimulus: On time: 300ms Off time: 300ms
		present_sentence(trial)

	# Present Task Word: On/Off time: inf
		if trial.cond != 'cons_str':
			answer, rt = present_answer(trial, correct_answer)
			correct = True if (correct_answer and answer == '1') or (not correct_answer and answer == '2') else False

			print("Correct?", correct)

		trialNum += 1

		exp.addData('participant', participant_name)
		exp.addData('trialnum', trialNum)
		exp.addData('stimulus', trial.stim)
		exp.addData('condition', trial.cond)
		exp.addData('correct', correct)
		exp.addData('reaction_time', rt)
		exp.addData('blockID', trial.blockID)


exp.nextEntry()
2

Hi there,

I think you want exp.nextEntry() indented to the same level as your exp.addData() calls. This will start a new row for each trial (within each block), whereas at the moment it is probably only starting a new row at the end of each block, meaning data rows from each trial are saving on top of one another.

Hope this helps,
Becca