for循环里else if如何作用于2个或以上循环？

老师们，请教一个用R里for循环结合if来修改文本名的问题:
res_S的内容如下:
`
Classification
1 kBacteria|suncultured_bacterium_pAKD4
2 kBacteria|sbacterium_enrichment_culture_clone_2a(2010)
3 kBacteria|pCandidatus_Gracilibacteria|sCandidatus_Gracilibacteria_bacterium_HOT-871
4 kBacteria|pCoprothermobacterota
2724 kBacteria|pActinobacteria|cActinobacteria
2725 kBacteria|pActinobacteria|cActinobacteria|oCorynebacteriales
6423 kViruses|oCaudovirales|fMyoviridae|sProchlorococcus_phage_P-TIM68
6424 kViruses|oCaudovirales|fMyoviridae|gBusanvirus|sAcidovorax_virus_ACP17
6920 kViruses|oCaudovirales|fSiphoviridae|gTimquatrovirus|sMycobacterium_phage_Keshu
6921 kViruses|oCaudovirales|fSiphoviridae|gTimquatrovirus|sMycobacterium_phage_Omnicron
6922 kViruses|oCaudovirales|fSiphoviridae|gTimquatrovirus|sMycobacterium_phage_ZoeJ
6923 kViruses|oCaudovirales|fSiphoviridae|sVerrucomicrobia_phage_P8625
6924 kViruses|oCaudovirales|fSiphoviridae|sAchromobacter_phage_JWF
6925 kViruses|oCaudovirales|fSiphoviridae|sTsukamurella_phage_TPA4
6926 kViruses|oCaudovirales|fSiphoviridae|sSynechococcus_phage_S-CBS2
6927 kViruses|oCaudovirales|fSiphoviridae|sArchaeal_BJ1_virus
6928 kViruses|oCaudovirales|fSiphoviridae|sMycobacterium_phage_Sparky
6929 kViruses|oCaudovirales|fSiphoviridae|sRhodococcus_phage_REQ2
6930 kViruses|oCaudovirales|fSiphoviridae|sGordonia_phage_Phinally
6931 kViruses|oCaudovirales|fSiphoviridae|sCaulobacter_phage_CcrColossus
6932 kViruses|oCaudovirales|fSiphoviridae|sGordonia_phage_GTE8

`

判断red_S的第一列是否含我想要的内容:
library(dplyr)
library(stringr)
flt_sp <- as.data.frame(str_detect(res_S[,1],"p__"))
flt_sc <- as.data.frame(str_detect(res_S[,1],"c__"))
flt_so <- as.data.frame(str_detect(res_S[,1],"o__"))
flt_sf <- as.data.frame(str_detect(res_S[,1],"f__"))
flt_sg <- as.data.frame(str_detect(res_S[,1],"g__"))

根据上述判断条件来增加res_S的内容:
for (i in 1:nrow(res_S)) {
if(flt_sp[i,1]=="FALSE"&&flt_sc[i,1]=="FALSE"&&flt_so[i,1]=="FALSE"&&flt_sf[i,1]=="FALSE"&&flt_sg[i,1]=="FALSE"){
sgs <- res_S[i,1]
res_S[i,1]=gsub("s__","1__22|a__155|b__n5e|g__uu6", sgs)##这里没问题
}else if(flt_sp[i,1]=="FALSE"&&flt_sc[i,1]=="FALSE"&&flt_so[i,1]=="TRUE"&&flt_sf[i,1]=="TRUE"&&flt_sg[i,1]=="FALSE"){
sgs <- res_S[i,1]
res_S[i,1]=gsub("o__","p__op|y__noname666|o__", sgs)###疑问1
res_S[i,1]=gsub("s__","gofw123t__noname|s__" ,sgs)###疑问2
}else {
res_S[i,1]=res_S[i,1]
}
}
结果发现，“###疑问2”更改了res_S对应的内容，但“###疑问1”这里没有起到作用，我把“###疑问2"这行代码删掉，然后“###疑问1”是可以更改res_S对应的内容，对比“###疑问0”，下面的“###疑问1”和“###疑问2”多了一行循环内容，我目前想到的办法是先执行“###疑问1”，然后再写另一个for循环执行“###疑问2”，我感觉这样很笨并且啰嗦，还请老师们给出个招，谢谢。

自我回答一下，将
`res_S[i,1]=gsub("o","pop|ynoname666|o", sgs)###疑问1

res_S[i,1]=gsub("s","gofw123tnoname|s__" ,sgs)###疑问2
`

改为
`
aa=gsub("o","pop|ynoname666|o", sgs)###疑问1

res_S[i,1]=gsub("s","gofw123tnoname|s__" ,aa)###疑问2
`

henrywangnl 抱歉，我刚刚疏忽了发帖规则，我的工作内容如下:我想要数据表第一列结构为：

k__aaa|p__sss|c__ddd|o__fppps|f__hbvbduvb|g__ssbcjb|s__dividvid

我们可以看到上面的内容是以“|”隔开，从k到s为7个级别，如上的内容是我想要的，但是，第一列有些行只为kaaa|sdddbjsvbbv，中间就少了psss|cddd|ofppps|fhbvbduvb|gssbcj等内容，因此我想判断第一列是否含有p或其他内容，若结果为FALSE，那么则根据c是否存在，若存在，则修改这一列这一行的内容为kaaa|pnoname|c已经存在的内容。总体上是这样，这是处理微生物数据格式的需求。我上面贴的代码，基本上是完整的。res_S的内容:

	class_sp	st1	st2	st3	st4	st5	st6	st7	st8	st9
1	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Verrucomicrobia_phage_P8625	1	0	0	0	1	0	0	0	0
2	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Achromobacter_phage_JWF	1	0	0	1	2	0	0	0	1
3	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Tsukamurella_phage_TPA4	1	0	0	1	0	0	1	1	0
4	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Synechococcus_phage_S-CBS2	1	0	1	0	0	0	0	0	0
5	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Archaeal_BJ1_virus	1	0	0	0	0	0	0	0	0
6	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Mycobacterium_phage_Sparky	1	4	2	0	0	1	0	0	0
7	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Rhodococcus_phage_REQ2	1	0	1	0	0	0	0	1	0
8	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Gordonia_phage_Phinally	1	0	0	0	0	0	0	0	0
9	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Caulobacter_phage_CcrColossus	2	1	2	3	1	2	1	2	2
10	k__Viruses|o__Caudovirales|f__Siphoviridae|s__Gordonia_phage_GTE8	2	2	0	2	0	0	0	1	0

```