我正在遵循文档(https://snakemake.readthedocs.io/en/stable/tutorial/advanced.html)中的教程，并且一直停留在"第4步:规则参数"上。锻炼。我想在我的params指令中使用通配符从我的配置文件中访问一个浮点数。
每当我在命令行中运行snakemake -np时，我似乎都会得到相同的错误:
InputFunctionException in line 46 of /mnt/c/Users/Matt/Desktop/snakemake-tutorial/Snakefile:
Error:
AttributeError: 'Wildcards' object has no attribute 'sample'
Wildcards:
Traceback:
File "/mnt/c/Users/Matt/Desktop/snakemake-tutorial/Snakefile", line 14, in get_bcftools_call_priors
这是我到目前为止的代码
import time
configfile: "config.yaml"
rule all:
input:
"plots/quals.svg"
def get_bwa_map_input_fastqs(wildcards):
print(wildcards.__dict__, 1, time.time()) #I have this print as a check
return config["samples"][wildcards.sample]
def get_bcftools_call_priors(wildcards):
print(wildcards.__dict__, 2, time.time()) #I have this print as a check
return config["prior_mutation_rates"][wildcards.sample]
rule bwa_map:
input:
"data/genome.fa",
get_bwa_map_input_fastqs
#lambda wildcards: config["samples"][wildcards.sample]
output:
"mapped_reads/{sample}.bam"
params:
rg=r"@RGtID:{sample}tSM:{sample}"
threads: 2
shell:
"bwa mem -R '{params.rg}' -t {threads} {input} | samtools view -Sb - > {output}"
rule samtools_sort:
input:
"mapped_reads/{sample}.bam"
output:
"sorted_reads/{sample}.bam"
shell:
"samtools sort -T sorted_reads/{wildcards.sample} "
"-O bam {input} > {output}"
rule samtools_index:
input:
"sorted_reads/{sample}.bam"
output:
"sorted_reads/{sample}.bam.bai"
shell:
"samtools index {input}"
rule bcftools_call:
input:
fa="data/genome.fa",
bam=expand("sorted_reads/{sample}.bam", sample=config["samples"]),
bai=expand("sorted_reads/{sample}.bam.bai", sample=config["samples"])
#prior=get_bcftools_call_priors
params:
prior=get_bcftools_call_priors
output:
"calls/all.vcf"
shell:
"samtools mpileup -g -f {input.fa} {input.bam} | "
"bcftools call -P {params.prior} -mv - > {output}"
rule plot_quals:
input:
"calls/all.vcf"
output:
"plots/quals.svg"
script:
"scripts/plot-quals.py"
这是config.yaml
samples:
A: data/samples/A.fastq
#B: data/samples/B.fastq
#C: data/samples/C.fastq
prior_mutation_rates:
A: 1.0e-4
#B: 1.0e-6
我不明白为什么我在bcftools_call中的输入函数调用说通配符对象是空的属性，但是在bwa_map中几乎相同的函数调用具有我想要的属性sample。从文档来看，通配符似乎会在运行任何东西之前传播，那么为什么缺少它呢?
这是命令行调用snakemake -np的完整输出:
{'_names': {'sample': (0, None)}, '_allowed_overrides': ['index', 'sort'], 'index': functools.partial(<function Namedlist._used_attribute at 0x7f91b1a58f70>, _name='index'), 'sort': functools.partial(<function Namedlist._used_attribute at 0x7f91b1a58f70>, _name='sort'), 'sample': 'A'} 1 1628877061.8831172
Job stats:
job count min threads max threads
-------------- ------- ------------- -------------
all 1 1 1
bcftools_call 1 1 1
bwa_map 1 1 1
plot_quals 1 1 1
samtools_index 1 1 1
samtools_sort 1 1 1
total 6 1 1
[Fri Aug 13 10:51:01 2021]
rule bwa_map:
input: data/genome.fa, data/samples/A.fastq
output: mapped_reads/A.bam
jobid: 4
wildcards: sample=A
resources: tmpdir=/tmp
bwa mem -R '@RGtID:AtSM:A' -t 1 data/genome.fa data/samples/A.fastq | samtools view -Sb - > mapped_reads/A.bam
[Fri Aug 13 10:51:01 2021]
rule samtools_sort:
input: mapped_reads/A.bam
output: sorted_reads/A.bam
jobid: 3
wildcards: sample=A
resources: tmpdir=/tmp
samtools sort -T sorted_reads/A -O bam mapped_reads/A.bam > sorted_reads/A.bam
[Fri Aug 13 10:51:01 2021]
rule samtools_index:
input: sorted_reads/A.bam
output: sorted_reads/A.bam.bai
jobid: 5
wildcards: sample=A
resources: tmpdir=/tmp
samtools index sorted_reads/A.bam
[Fri Aug 13 10:51:01 2021]
rule bcftools_call:
input: data/genome.fa, sorted_reads/A.bam, sorted_reads/A.bam.bai
output: calls/all.vcf
jobid: 2
resources: tmpdir=/tmp
{'_names': {}, '_allowed_overrides': ['index', 'sort'], 'index': functools.partial(<function Namedlist._used_attribute at 0x7f91b1a58f70>, _name='index'), 'sort': functools.partial(<function Namedlist._used_attribute at 0x7f91b1a58f70>, _name='sort')} 2 1628877061.927639
InputFunctionException in line 46 of /mnt/c/Users/Matt/Desktop/snakemake-tutorial/Snakefile:
Error:
AttributeError: 'Wildcards' object has no attribute 'sample'
Wildcards:
Traceback:
File "/mnt/c/Users/Matt/Desktop/snakemake-tutorial/Snakefile", line 14, in get_bcftools_call_priors
config.yaml中获取到不同的指令中，我将很乐意欣赏这些提示。
编辑:我在网上搜索了很多，但还没有理解这个问题。
每个规则的通配符都基于该规则的输出文件。规则bcftools_call有一个输出文件(calls/all.vcf)，它没有通配符。因此，当get_bcftools_call_priors被调用时，当它试图访问未设置的wildcards.sample属性时，它会抛出一个异常。
你应该在你的配置文件中设置一个全局的prior_mutation_rate，然后在bcftools_call规则中访问它:
rule bcftools_call:
...
params:
prior=config["prior_mutation_rate"],