Package 'GrabSVG'

Title: Granularity-Based Spatially Variable Genes Identifications
Description: Identifying spatially variable genes is critical in linking molecular cell functions with tissue phenotypes. This package implemented a granularity-based dimension-agnostic tool for the identification of spatially variable genes. The detailed description of this method is available at Wang, J. and Li, J. et al. 2023 (Wang, J. and Li, J. (2023), <doi:10.1038/s41467-023-43256-5>).
Authors: Jinpu Li [aut, cre]
Maintainer: Jinpu Li <[email protected]>
License: GPL (>= 2)
Version: 0.0.2
Built: 2024-11-02 03:26:32 UTC
Source: https://github.com/cran/GrabSVG

Help Index


A Granularity-Based Approach to identify Spatially Variable Genes

Description

This function is designed to identify spatially variable genes through a granularity-based approach.

Usage

GrabSVG(Coords, ExpMat_Sp, D_1 = 1.0, D_2 = 3.0, 
Exp_Norm = TRUE, Coords_Norm_Method = c("Sliced", "Overall", "None"))

Arguments

Coords

A M x D matrix representing D-dimensional coordinates for M spots

ExpMat_Sp

A sparse, N x M expression matrix in dgCMatrix class with N genes and M spots

D_1

Size of the small patch

D_2

Size of the big patch

Exp_Norm

A Boolean value indicating whether the expression matrix should be normalized

Coords_Norm_Method

Normalization method for the coordinates matrix, which can be "None", "Sliced", or "Overall".

Details

This function utilizes a MxD matrix (Coords) representing D-dimensional coordinates with M spots and a sparse, NxM expression matrix (ExpMat_Sp) with N genes and M spots.

Value

A data frame with the name of genes and corresponding p-values.

Examples

Coords <- expand.grid(1:100,1:100, 1:3)
RandFunc <- function(n) floor(10 * stats::rbeta(n, 1, 5))
Raw_Exp <- Matrix::rsparsematrix(nrow = 10^4, ncol = 3*10^4, density = 0.0001, rand.x = RandFunc)
Filtered_ExpMat <- SpFilter(Raw_Exp)
rownames(Filtered_ExpMat) <- paste0("Gene_", 1:nrow(Filtered_ExpMat))
P_values <- GrabSVG(Coords, Filtered_ExpMat)

Loading data from a Seurat object or a data frame.

Description

A function to load and filter data from a Seurat object or a data frame.

Usage

LoadSpatial(InputData, Dimension = 2)

Arguments

InputData

A Seurat spatial object or a M x (D + N) data matrix representing the D-dimensional coordinates and expressions of N genes on M spots. The coordinates should be placed at the first D columns

Dimension

The dimension of coordinates

Value

A list of two data frame:

Coords

A M x D matrix representing D-dimensional coordinates for M spots

ExpMatrix

A sparse, N x M expression matrix in dgCMatrix class with N genes and M spots


A function for filtering low expressed genes

Description

A function for filtering low expressed genes

Usage

SpFilter(ExpMat_Sp, Threshold = 5)

Arguments

ExpMat_Sp

A sparse, N x M expression matrix in dgCMatrix class with N genes and M spots

Threshold

A threshold set to filter out genes with a total read count below this specified value

Value

A sparse expression matrix in dgCMatrix class

Examples

# create a sparse expression matrix
Raw_ExpMat <- Matrix::rsparsematrix(nrow = 10000, ncol = 2000, 
density = 0.01, rand.x = function(n) rpois(n, 15))
Filtered_ExpMat <- SpFilter(Raw_ExpMat)