This function is for multi-group lipid characteristics analysis. It identifies the differentially expressed lipid characteristics based on the user-selected characteristic.
Arguments
- processed_se
- A SummarizedExperiment object constructed by - as_summarized_experimentand processed by- data_process.
- char
- Character. A lipid characteristic selected from the deChar list returned by - list_lipid_char.
- ref_group
- Character. Group name of the reference group. It must be one of the group names in the group information table's group column. 
- post_hoc
- Character. The method to statistic calculation. Allowed method include "One-way ANOVA" and "Kruskal-Wallis test". Default is - 'One-way ANOVA'.
- post_hoc_sig
- Character. The p-value to be used for the statistically significant. Must be one of "pval" or "padj". Default is - 'pval'.
- post_hoc_p_cutoff
- Numeric. Significant level. Default is - 0.05.
- transform
- Character. Method for data transformation. Allowed methods include "none", "log10", "square", "cube", "log2". Select 'none' to skip data transformation. Default is - 'log10'.
Examples
data("se_multiGroup")
processed_se <- data_process(
    se=se_multiGroup, exclude_missing=TRUE, exclude_missing_pct=70,
    replace_na_method='min', replace_na_method_ref=0.5,
    normalization='Percentage', transform='log10')
char_list <- list_lipid_char(processed_se)$deChar_list
#> There are 4 ratio characteristics that can be converted in your dataset.
print(char_list)
#>                               Lipid classification 
#>                                         "Category" 
#>                               Lipid classification 
#>                                       "Main.Class" 
#>                               Lipid classification 
#>                                        "Sub.Class" 
#>                               Lipid classification 
#>                                            "class" 
#>                              Fatty acid properties 
#>                                               "FA" 
#>                              Fatty acid properties 
#>                                             "FA.C" 
#>                              Fatty acid properties 
#>                        "FA.Chain.Length.Category1" 
#>                              Fatty acid properties 
#>                        "FA.Chain.Length.Category2" 
#>                              Fatty acid properties 
#>                        "FA.Chain.Length.Category3" 
#>                              Fatty acid properties 
#>                                            "FA.DB" 
#>                              Fatty acid properties 
#>                                            "FA.OH" 
#>                              Fatty acid properties 
#>                        "FA.Unsaturation.Category1" 
#>                              Fatty acid properties 
#>                        "FA.Unsaturation.Category2" 
#>                              Fatty acid properties 
#>                                          "Total.C" 
#>                              Fatty acid properties 
#>                                         "Total.DB" 
#>                              Fatty acid properties 
#>                                         "Total.FA" 
#>                              Fatty acid properties 
#>                                         "Total.OH" 
#>                    Physical or chemical properties 
#>                                "Bilayer.Thickness" 
#>                    Physical or chemical properties 
#>                                 "Headgroup.Charge" 
#>                    Physical or chemical properties 
#>                              "Intrinsic.Curvature" 
#>                    Physical or chemical properties 
#>                                "Lateral.Diffusion" 
#>                    Physical or chemical properties 
#>                           "Transition.Temperature" 
#>                                 Cellular component 
#>                               "Cellular.Component" 
#>                                           Function 
#>                                         "Function" 
#>                                    Specific ratios 
#>                  "Chains Ether/Ester linked ratio" 
#>                                    Specific ratios 
#>                            "Chains odd/even ratio" 
#>                                    Specific ratios 
#>      "Ratio of Lysophospholipids to Phospholipids" 
#>                                    Specific ratios 
#> "Ratio of specific lipid class A to lipid class B" 
deChar_se <- deChar_multiGroup(
    processed_se, char='class', ref_group='ctrl', post_hoc='One-way ANOVA',
    post_hoc_sig='pval', post_hoc_p_cutoff=0.05, transform='log10')
#> There are 4 ratio characteristics that can be converted in your dataset.