[update] Reduce unnecessary copying of arrays

[micchu]

To save memory, unnecessary array copies were removed.

[github-actions[bot]]

Coverage Report

File	Stmts	Miss	Cover	Missing
bdpy
__init__.py	3	3	0%	9–11
bdpy/bdata
__init__.py	2	2	0%	7–8
bdata.py	402	402	0%	26–924
featureselector.py	64	64	0%	8–124
metadata.py	67	67	0%	8–154
utils.py	113	113	0%	4–258
bdpy/dataform
__init__.py	4	4	0%	7–10
datastore.py	107	107	0%	7–265
features.py	272	272	0%	8–522
pd.py	9	9	0%	7–44
sparse.py	67	67	0%	6–126
bdpy/distcomp
__init__.py	1	1	0%	6
distcomp.py	92	92	0%	7–127
bdpy/dl
caffe.py	60	60	0%	4–129
bdpy/dl/torch
__init__.py	2	2	0%	1–2
base.py	43	43	0%	6–105
models.py	332	332	0%	4–874
torch.py	109	109	0%	3–258
bdpy/evals
metrics.py	95	95	0%	3–179
bdpy/feature
__init__.py	1	1	0%	3
feature.py	30	30	0%	1–74
bdpy/fig
__init__.py	4	4	0%	6–9
draw_group_image_set.py	90	90	0%	3–182
fig.py	88	88	0%	16–164
makeplots.py	336	336	0%	1–729
tile_images.py	59	59	0%	1–193
bdpy/ml
__init__.py	7	7	0%	8–14
crossvalidation.py	59	59	0%	7–196
ensemble.py	13	13	0%	5–46
learning.py	308	308	0%	4–613
model.py	140	140	0%	4–285
regress.py	11	11	0%	6–38
searchlight.py	16	16	0%	4–51
bdpy/mri
__init__.py	7	7	0%	7–13
fmriprep.py	497	497	0%	4–866
glm.py	40	40	0%	4–95
image.py	24	24	0%	4–54
load_epi.py	28	28	0%	7–88
load_mri.py	19	19	0%	4–36
roi.py	248	248	0%	4–499
spm.py	158	158	0%	1–300
bdpy/opendata
__init__.py	1	1	0%	1
openneuro.py	210	210	0%	1–329
bdpy/preproc
__init__.py	3	3	0%	8–10
interface.py	52	52	0%	8–217
preprocessor.py	129	129	0%	8–236
select_top.py	22	22	0%	8–61
util.py	6	6	0%	6–22
bdpy/recon
utils.py	55	55	0%	4–146
bdpy/recon/torch
__init__.py	1	1	0%	1
icnn.py	161	161	0%	15–478
bdpy/stats
__init__.py	1	1	0%	13
corr.py	43	43	0%	6–112
bdpy/util
__init__.py	3	3	0%	7–9
info.py	47	47	0%	4–79
math.py	13	13	0%	4–38
utils.py	36	36	0%	7–145
TOTAL	4810	4810	0%

Tests	Skipped	Failures	Errors	Time
110	0 :zzz:	13 :x:	6 :fire:	13.799s :stopwatch: