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<header>
<h1 class="title">Module <code>VITAE.preprocess</code></h1>
</header>
<section id="section-intro">
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python"># -*- coding: utf-8 -*-
from typing import Optional
import numpy as np
import pandas as pd
from skmisc import loess
from sklearn import preprocessing
import warnings
from sklearn.decomposition import PCA
from VITAE.utils import _check_expression, _check_variability
def normalize_gene_expression(x, K : float = 1e4, transform_fn : str = 'log'):
'''Normalize the gene expression counts for each cell by the total expression counts,
divide this by a size scale factor, which is determined by total counts and a constant K
then log-transforms the result.
Parameters
----------
x : np.array
\([N, G^{raw}]\) The raw count data.
K : float, optional
The normalizing constant.
transform_fn : str, optional
Either 'log' or 'sqrt'.
Returns
----------
x_normalized : np.array
\([N, G^{raw}]\) The log-normalized data.
scale_factor : np.array
\([N, ]\) The scale factors.
'''
scale_factor = np.sum(x,axis=1, keepdims=True)/K
if transform_fn=='log':
x_normalized = np.log(x/scale_factor + 1)
else:
x_normalized = np.where(x>0, np.sqrt(x/scale_factor), 0)
print('min normalized value: ' + str(np.min(x_normalized)))
print('max normalized value: ' + str(np.max(x_normalized)))
return x_normalized, scale_factor
def feature_select(x, gene_num : int = 2000):
'''Select highly variable genes (HVGs)
(See [Stuart *et al*, (2019)](https://www.nature.com/articles/nbt.4096) and its early version [preprint](https://www.biorxiv.org/content/10.1101/460147v1.full.pdf)
Page 12-13: Data preprocessing - Feature selection for individual datasets).
Parameters
----------
x : np.array
\([N, G^{raw}]\) The raw count data.
gene_num : int, optional
The number of genes to retain.
Returns
----------
x : np.array
\([N, G]\) The count data after gene selection.
index : np.array
\([G, ]\) The selected index of genes.
'''
n, p = x.shape
# mean and variance of each gene of the unnormalized data
mean, var = np.mean(x, axis=0), np.var(x, axis=0, ddof=1)
# model log10(var)~log10(mean) by local fitting of polynomials of degree 2
loess_model = loess.loess(np.log10(mean), np.log10(var),
span = 0.3, degree = 2, family='gaussian'
)
loess_model.fit()
fitted = loess_model.outputs.fitted_values
# standardized feature
z = (x - mean)/np.sqrt(10**fitted)
# clipped the standardized features to remove outliers
z = np.clip(z, -np.inf, np.sqrt(n))
# the variance of standardized features across all cells represents a measure of
# single cell dispersion after controlling for mean expression
feature_score = np.sum(z**2, axis=0)/(n-1)
# feature selection
index = feature_score.argsort()[::-1][0:gene_num]
return x[:, index], index
def preprocess(adata = None, processed: bool = False, dimred: bool = False,
x = None, c = None, label_names = None, raw_cell_names = None, raw_gene_names = None,
K: float = 1e4, transform_fn: str = 'log', gene_num: int = 2000, data_type: str = 'UMI',
npc: int = 64, random_state=0):
'''Preprocess count data.
Parameters
----------
adata : AnnData, optional
The scanpy object.
processed : boolean
Whether adata has been processed.
dimred : boolean
Whether the processed adata is after dimension reduction.
x : np.array, optional
\([N^{raw}, G^{raw}]\) The raw count matrix.
c : np.array
\([N^{raw}, s]\) The covariate matrix.
label_names : np.array
\([N^{raw}, ]\) The true or estimated cell types.
raw_cell_names : np.array
\([N^{raw}, ]\) The names of cells.
raw_gene_names : np.array
\([G^{raw}, ]\) The names of genes.
K : int, optional
The normalizing constant.
transform_fn : str
The transform function used to normalize the gene expression after scaling. Either 'log' or 'sqrt'.
gene_num : int, optional
The number of genes to retain.
data_type : str, optional
'UMI', 'non-UMI', or 'Gaussian'.
npc : int, optional
The number of PCs to retain, only used if `data_type='Gaussian'`.
random_state : int, optional
The random state for PCA. With different random states, the resulted PCA scores are slightly different.
Returns
----------
x_normalized : np.array
\([N, G]\) The preprocessed matrix.
expression : np.array
\([N, G^{raw}]\) The expression matrix after log-normalization and before scaling.
x : np.array
\([N, G]\) The raw count matrix after gene selections.
c : np.array
\([N, s]\) The covariates.
cell_names : np.array
\([N, ]\) The cell names.
gene_names : np.array
\([G^{raw}, ]\) The gene names.
selected_gene_names :
\([G, ]\) The selected gene names.
scale_factor :
\([N, ]\) The scale factors.
labels : np.array
\([N, ]\) The encoded labels.
label_names : np.array
\([N, ]\) The label names.
le : sklearn.preprocessing.LabelEncoder
The label encoder.
gene_scalar : sklearn.preprocessing.StandardScaler
The gene scaler.
'''
# if input is a scanpy data
if adata is not None:
import scanpy as sc
# if the input scanpy is processed
if processed:
x_normalized = x = adata.X
gene_names = adata.var_names.values
expression = None
scale_factor = np.ones(x.shape[0])
# if the input scanpy is not processed
else:
dimred = False
x = adata.X.copy()
adata, expression, gene_names, cell_mask, gene_mask, gene_mask2 = _recipe_seurat(adata, gene_num)
x_normalized = adata.X.copy()
scale_factor = adata.obs.counts_per_cell.values / 1e4
x = x[cell_mask,:][:,gene_mask][:,gene_mask2]
if label_names is None:
try:
label_names = adata.obs.cell_types
except:
if label_names is not None and processed is False:
label_names = label_names[cell_mask]
cell_names = adata.obs_names.values
selected_gene_names = adata.var_names.values
gene_scalar = None
# if input is a count matrix
else:
# remove cells that have no expression
expressed = _check_expression(x)
print('Removing %d cells without expression.'%(np.sum(expressed==0)))
x = x[expressed==1,:]
if c is not None:
c = c[expressed==1,:]
if label_names is not None:
label_names = label_names[expressed==1]
# remove genes without variability
variable = _check_variability(x)
print('Removing %d genes without variability.'%(np.sum(variable==0)))
x = x[:, variable==1]
gene_names = raw_gene_names[variable==1]
# log-normalization
expression, scale_factor = normalize_gene_expression(x, K, transform_fn)
# feature selection
x, index = feature_select(x, gene_num)
selected_expression = expression[:, index]
# per-gene standardization
gene_scalar = preprocessing.StandardScaler()
x_normalized = gene_scalar.fit_transform(selected_expression)
cell_names = raw_cell_names[expressed==1]
selected_gene_names = gene_names[index]
if (data_type=='Gaussian') and (dimred is False):
# use arpack solver and extend precision to get deterministic result
pca = PCA(n_components = npc, random_state=random_state, svd_solver='arpack')
x_normalized = x = pca.fit_transform(x_normalized.astype(np.float64)).astype(np.float32)
if c is not None:
c_scalar = preprocessing.StandardScaler()
c = c_scalar.fit_transform(c)
if label_names is None:
warnings.warn('No labels for cells!')
labels = None
le = None
else:
le = preprocessing.LabelEncoder()
labels = le.fit_transform(label_names)
print('Number of cells in each class: ')
table = pd.value_counts(label_names)
table.index = pd.Series(le.transform(table.index).astype(str)) \
+ ' <---> ' + table.index
table = table.sort_index()
print(table)
return (x_normalized, expression, x, c,
cell_names, gene_names, selected_gene_names,
scale_factor, labels, label_names, le, gene_scalar)
def _recipe_seurat(adata, gene_num):
"""
Normalization and filtering as of Seurat [Satija15]_.
This uses a particular preprocessing
"""
import scanpy as sc
cell_mask = sc.pp.filter_cells(adata, min_genes=200, inplace=False)[0]
adata = adata[cell_mask,:]
gene_mask = sc.pp.filter_genes(adata, min_cells=3, inplace=False)[0]
adata = adata[:,gene_mask]
gene_names = adata.var_names.values
sc.pp.normalize_total(adata, target_sum=1e4, key_added='counts_per_cell')
filter_result = sc.pp.filter_genes_dispersion(
adata.X, min_mean=0.0125, max_mean=3, min_disp=0.5, log=False, n_top_genes=gene_num)
sc.pp.log1p(adata)
expression = adata.X.copy()
adata._inplace_subset_var(filter_result.gene_subset) # filter genes
sc.pp.scale(adata, max_value=10)
return adata, expression, gene_names, cell_mask, gene_mask, filter_result.gene_subset</code></pre>
</details>
</section>
<section>
</section>
<section>
</section>
<section>
<h2 class="section-title" id="header-functions">Functions</h2>
<dl>
<dt id="VITAE.preprocess.normalize_gene_expression"><code class="name flex">
<span>def <span class="ident">normalize_gene_expression</span></span>(<span>x, K: float = 10000.0, transform_fn: str = 'log')</span>
</code></dt>
<dd>
<div class="desc"><p>Normalize the gene expression counts for each cell by the total expression counts,
divide this by a size scale factor, which is determined by total counts and a constant K
then log-transforms the result.</p>
<h2 id="parameters">Parameters</h2>
<dl>
<dt><strong><code>x</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G^{raw}]</span><script type="math/tex">[N, G^{raw}]</script></span> The raw count data.</dd>
<dt><strong><code>K</code></strong> : <code>float</code>, optional</dt>
<dd>The normalizing constant.</dd>
<dt><strong><code>transform_fn</code></strong> : <code>str</code>, optional</dt>
<dd>Either 'log' or 'sqrt'.</dd>
</dl>
<h2 id="returns">Returns</h2>
<dl>
<dt><strong><code>x_normalized</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G^{raw}]</span><script type="math/tex">[N, G^{raw}]</script></span> The log-normalized data.</dd>
<dt><strong><code>scale_factor</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, ]</span><script type="math/tex">[N, ]</script></span> The scale factors.</dd>
</dl></div>
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python">def normalize_gene_expression(x, K : float = 1e4, transform_fn : str = 'log'):
'''Normalize the gene expression counts for each cell by the total expression counts,
divide this by a size scale factor, which is determined by total counts and a constant K
then log-transforms the result.
Parameters
----------
x : np.array
\([N, G^{raw}]\) The raw count data.
K : float, optional
The normalizing constant.
transform_fn : str, optional
Either 'log' or 'sqrt'.
Returns
----------
x_normalized : np.array
\([N, G^{raw}]\) The log-normalized data.
scale_factor : np.array
\([N, ]\) The scale factors.
'''
scale_factor = np.sum(x,axis=1, keepdims=True)/K
if transform_fn=='log':
x_normalized = np.log(x/scale_factor + 1)
else:
x_normalized = np.where(x>0, np.sqrt(x/scale_factor), 0)
print('min normalized value: ' + str(np.min(x_normalized)))
print('max normalized value: ' + str(np.max(x_normalized)))
return x_normalized, scale_factor</code></pre>
</details>
</dd>
<dt id="VITAE.preprocess.feature_select"><code class="name flex">
<span>def <span class="ident">feature_select</span></span>(<span>x, gene_num: int = 2000)</span>
</code></dt>
<dd>
<div class="desc"><p>Select highly variable genes (HVGs)
(See <a href="https://www.nature.com/articles/nbt.4096">Stuart <em>et al</em>, (2019)</a> and its early version <a href="https://www.biorxiv.org/content/10.1101/460147v1.full.pdf">preprint</a>
Page 12-13: Data preprocessing - Feature selection for individual datasets).</p>
<h2 id="parameters">Parameters</h2>
<dl>
<dt><strong><code>x</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G^{raw}]</span><script type="math/tex">[N, G^{raw}]</script></span> The raw count data.</dd>
<dt><strong><code>gene_num</code></strong> : <code>int</code>, optional</dt>
<dd>The number of genes to retain.</dd>
</dl>
<h2 id="returns">Returns</h2>
<dl>
<dt><strong><code>x</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G]</span><script type="math/tex">[N, G]</script></span> The count data after gene selection.</dd>
<dt><strong><code>index</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[G, ]</span><script type="math/tex">[G, ]</script></span> The selected index of genes.</dd>
</dl></div>
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python">def feature_select(x, gene_num : int = 2000):
'''Select highly variable genes (HVGs)
(See [Stuart *et al*, (2019)](https://www.nature.com/articles/nbt.4096) and its early version [preprint](https://www.biorxiv.org/content/10.1101/460147v1.full.pdf)
Page 12-13: Data preprocessing - Feature selection for individual datasets).
Parameters
----------
x : np.array
\([N, G^{raw}]\) The raw count data.
gene_num : int, optional
The number of genes to retain.
Returns
----------
x : np.array
\([N, G]\) The count data after gene selection.
index : np.array
\([G, ]\) The selected index of genes.
'''
n, p = x.shape
# mean and variance of each gene of the unnormalized data
mean, var = np.mean(x, axis=0), np.var(x, axis=0, ddof=1)
# model log10(var)~log10(mean) by local fitting of polynomials of degree 2
loess_model = loess.loess(np.log10(mean), np.log10(var),
span = 0.3, degree = 2, family='gaussian'
)
loess_model.fit()
fitted = loess_model.outputs.fitted_values
# standardized feature
z = (x - mean)/np.sqrt(10**fitted)
# clipped the standardized features to remove outliers
z = np.clip(z, -np.inf, np.sqrt(n))
# the variance of standardized features across all cells represents a measure of
# single cell dispersion after controlling for mean expression
feature_score = np.sum(z**2, axis=0)/(n-1)
# feature selection
index = feature_score.argsort()[::-1][0:gene_num]
return x[:, index], index</code></pre>
</details>
</dd>
<dt id="VITAE.preprocess.preprocess"><code class="name flex">
<span>def <span class="ident">preprocess</span></span>(<span>adata=None, processed: bool = False, dimred: bool = False, x=None, c=None, label_names=None, raw_cell_names=None, raw_gene_names=None, K: float = 10000.0, transform_fn: str = 'log', gene_num: int = 2000, data_type: str = 'UMI', npc: int = 64, random_state=0)</span>
</code></dt>
<dd>
<div class="desc"><p>Preprocess count data.</p>
<h2 id="parameters">Parameters</h2>
<dl>
<dt><strong><code>adata</code></strong> : <code>AnnData</code>, optional</dt>
<dd>The scanpy object.</dd>
<dt><strong><code>processed</code></strong> : <code>boolean</code></dt>
<dd>Whether adata has been processed.</dd>
<dt><strong><code>dimred</code></strong> : <code>boolean</code></dt>
<dd>Whether the processed adata is after dimension reduction.</dd>
<dt><strong><code>x</code></strong> : <code>np.array</code>, optional</dt>
<dd><span><span class="MathJax_Preview">[N^{raw}, G^{raw}]</span><script type="math/tex">[N^{raw}, G^{raw}]</script></span> The raw count matrix.</dd>
<dt><strong><code>c</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N^{raw}, s]</span><script type="math/tex">[N^{raw}, s]</script></span> The covariate matrix.</dd>
<dt><strong><code>label_names</code></strong> : <code>np.array </code></dt>
<dd><span><span class="MathJax_Preview">[N^{raw}, ]</span><script type="math/tex">[N^{raw}, ]</script></span> The true or estimated cell types.</dd>
<dt><strong><code>raw_cell_names</code></strong> : <code>np.array
</code></dt>
<dd><span><span class="MathJax_Preview">[N^{raw}, ]</span><script type="math/tex">[N^{raw}, ]</script></span> The names of cells.</dd>
<dt><strong><code>raw_gene_names</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[G^{raw}, ]</span><script type="math/tex">[G^{raw}, ]</script></span> The names of genes.</dd>
<dt><strong><code>K</code></strong> : <code>int</code>, optional</dt>
<dd>The normalizing constant.</dd>
<dt><strong><code>transform_fn</code></strong> : <code>str</code></dt>
<dd>The transform function used to normalize the gene expression after scaling. Either 'log' or 'sqrt'.</dd>
<dt><strong><code>gene_num</code></strong> : <code>int</code>, optional</dt>
<dd>The number of genes to retain.</dd>
<dt><strong><code>data_type</code></strong> : <code>str</code>, optional</dt>
<dd>'UMI', 'non-UMI', or 'Gaussian'.</dd>
<dt><strong><code>npc</code></strong> : <code>int</code>, optional</dt>
<dd>The number of PCs to retain, only used if <code>data_type='Gaussian'</code>.</dd>
<dt><strong><code>random_state</code></strong> : <code>int</code>, optional</dt>
<dd>The random state for PCA. With different random states, the resulted PCA scores are slightly different.</dd>
</dl>
<h2 id="returns">Returns</h2>
<dl>
<dt><strong><code>x_normalized</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G]</span><script type="math/tex">[N, G]</script></span> The preprocessed matrix.</dd>
<dt><strong><code>expression</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G^{raw}]</span><script type="math/tex">[N, G^{raw}]</script></span> The expression matrix after log-normalization and before scaling.</dd>
<dt><strong><code>x</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, G]</span><script type="math/tex">[N, G]</script></span> The raw count matrix after gene selections.</dd>
<dt><strong><code>c</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, s]</span><script type="math/tex">[N, s]</script></span> The covariates.</dd>
<dt><strong><code>cell_names</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, ]</span><script type="math/tex">[N, ]</script></span> The cell names.</dd>
<dt><strong><code>gene_names</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[G^{raw}, ]</span><script type="math/tex">[G^{raw}, ]</script></span> The gene names.</dd>
<dt><strong><code>selected_gene_names</code></strong></dt>
<dd><span><span class="MathJax_Preview">[G, ]</span><script type="math/tex">[G, ]</script></span> The selected gene names.</dd>
<dt><strong><code>scale_factor</code></strong></dt>
<dd><span><span class="MathJax_Preview">[N, ]</span><script type="math/tex">[N, ]</script></span> The scale factors.</dd>
<dt><strong><code>labels</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, ]</span><script type="math/tex">[N, ]</script></span> The encoded labels.</dd>
<dt><strong><code>label_names</code></strong> : <code>np.array</code></dt>
<dd><span><span class="MathJax_Preview">[N, ]</span><script type="math/tex">[N, ]</script></span> The label names.</dd>
<dt><strong><code>le</code></strong> : <code>sklearn.preprocessing.LabelEncoder</code></dt>
<dd>The label encoder.</dd>
<dt><strong><code>gene_scalar</code></strong> : <code>sklearn.preprocessing.StandardScaler</code></dt>
<dd>The gene scaler.</dd>
</dl></div>
<details class="source">
<summary>
<span>Expand source code</span>
</summary>
<pre><code class="python">def preprocess(adata = None, processed: bool = False, dimred: bool = False,
x = None, c = None, label_names = None, raw_cell_names = None, raw_gene_names = None,
K: float = 1e4, transform_fn: str = 'log', gene_num: int = 2000, data_type: str = 'UMI',
npc: int = 64, random_state=0):
'''Preprocess count data.
Parameters
----------
adata : AnnData, optional
The scanpy object.
processed : boolean
Whether adata has been processed.
dimred : boolean
Whether the processed adata is after dimension reduction.
x : np.array, optional
\([N^{raw}, G^{raw}]\) The raw count matrix.
c : np.array
\([N^{raw}, s]\) The covariate matrix.
label_names : np.array
\([N^{raw}, ]\) The true or estimated cell types.
raw_cell_names : np.array
\([N^{raw}, ]\) The names of cells.
raw_gene_names : np.array
\([G^{raw}, ]\) The names of genes.
K : int, optional
The normalizing constant.
transform_fn : str
The transform function used to normalize the gene expression after scaling. Either 'log' or 'sqrt'.
gene_num : int, optional
The number of genes to retain.
data_type : str, optional
'UMI', 'non-UMI', or 'Gaussian'.
npc : int, optional
The number of PCs to retain, only used if `data_type='Gaussian'`.
random_state : int, optional
The random state for PCA. With different random states, the resulted PCA scores are slightly different.
Returns
----------
x_normalized : np.array
\([N, G]\) The preprocessed matrix.
expression : np.array
\([N, G^{raw}]\) The expression matrix after log-normalization and before scaling.
x : np.array
\([N, G]\) The raw count matrix after gene selections.
c : np.array
\([N, s]\) The covariates.
cell_names : np.array
\([N, ]\) The cell names.
gene_names : np.array
\([G^{raw}, ]\) The gene names.
selected_gene_names :
\([G, ]\) The selected gene names.
scale_factor :
\([N, ]\) The scale factors.
labels : np.array
\([N, ]\) The encoded labels.
label_names : np.array
\([N, ]\) The label names.
le : sklearn.preprocessing.LabelEncoder
The label encoder.
gene_scalar : sklearn.preprocessing.StandardScaler
The gene scaler.
'''
# if input is a scanpy data
if adata is not None:
import scanpy as sc
# if the input scanpy is processed
if processed:
x_normalized = x = adata.X
gene_names = adata.var_names.values
expression = None
scale_factor = np.ones(x.shape[0])
# if the input scanpy is not processed
else:
dimred = False
x = adata.X.copy()
adata, expression, gene_names, cell_mask, gene_mask, gene_mask2 = _recipe_seurat(adata, gene_num)
x_normalized = adata.X.copy()
scale_factor = adata.obs.counts_per_cell.values / 1e4
x = x[cell_mask,:][:,gene_mask][:,gene_mask2]
if label_names is None:
try:
label_names = adata.obs.cell_types
except:
if label_names is not None and processed is False:
label_names = label_names[cell_mask]
cell_names = adata.obs_names.values
selected_gene_names = adata.var_names.values
gene_scalar = None
# if input is a count matrix
else:
# remove cells that have no expression
expressed = _check_expression(x)
print('Removing %d cells without expression.'%(np.sum(expressed==0)))
x = x[expressed==1,:]
if c is not None:
c = c[expressed==1,:]
if label_names is not None:
label_names = label_names[expressed==1]
# remove genes without variability
variable = _check_variability(x)
print('Removing %d genes without variability.'%(np.sum(variable==0)))
x = x[:, variable==1]
gene_names = raw_gene_names[variable==1]
# log-normalization
expression, scale_factor = normalize_gene_expression(x, K, transform_fn)
# feature selection
x, index = feature_select(x, gene_num)
selected_expression = expression[:, index]
# per-gene standardization
gene_scalar = preprocessing.StandardScaler()
x_normalized = gene_scalar.fit_transform(selected_expression)
cell_names = raw_cell_names[expressed==1]
selected_gene_names = gene_names[index]
if (data_type=='Gaussian') and (dimred is False):
# use arpack solver and extend precision to get deterministic result
pca = PCA(n_components = npc, random_state=random_state, svd_solver='arpack')
x_normalized = x = pca.fit_transform(x_normalized.astype(np.float64)).astype(np.float32)
if c is not None:
c_scalar = preprocessing.StandardScaler()
c = c_scalar.fit_transform(c)
if label_names is None:
warnings.warn('No labels for cells!')
labels = None
le = None
else:
le = preprocessing.LabelEncoder()
labels = le.fit_transform(label_names)
print('Number of cells in each class: ')
table = pd.value_counts(label_names)
table.index = pd.Series(le.transform(table.index).astype(str)) \
+ ' <---> ' + table.index
table = table.sort_index()
print(table)
return (x_normalized, expression, x, c,
cell_names, gene_names, selected_gene_names,
scale_factor, labels, label_names, le, gene_scalar)</code></pre>
</details>
</dd>
</dl>
</section>
<section>
</section>
</article>
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