fix error in IA when nomodel

workflow/rules/compute_frip.rules

-#########################################################################
-# ePeak: Standardize and reproducible ChIP-seq analysis from raw        #
-#           data to differential analysis                               #
-# Authors: Rachel Legendre, Maelle Daunesse                             #
-# Copyright (c) 2019-2020  Institut Pasteur (Paris) and CNRS.           #
-#                                                                       #
-# This file is part of ePeak workflow.                                  #
-#                                                                       #
-# ePeak is free software: you can redistribute it and/or modify         #
-# it under the terms of the GNU General Public License as published by  #
-# the Free Software Foundation, either version 3 of the License, or     #
-# (at your option) any later version.                                   #
-#                                                                       #
-# ePeak is distributed in the hope that it will be useful,              #
-# but WITHOUT ANY WARRANTY; without even the implied warranty of        #
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the          #
-# GNU General Public License for more details .                         #
-#                                                                       #
-# You should have received a copy of the GNU General Public License     #
-# along with ePeak (LICENSE).                                           #
-# If not, see <https://www.gnu.org/licenses/>.                          #
-#########################################################################
-
-
-rule compute_frip:
-    input:
-        bam = compute_frip_bam,
-        bed = compute_frip_peaks
-    output:
-        compute_frip_csv
-    params:
-        paired = compute_frip_paired
-    singularity:
-        "epeak.img"
-    log:
-        out = compute_frip_log
-    shell:
-        """
-        temp_file=$(mktemp)
-
-        if [[ {params.paired} == "True" ]]
-        then
-            #write reads as bedpe bed file to get fragments instead of reads
-            bedtools bamtobed -bedpe -i {input.bam} > $temp_file 
-        else
-            bedtools bamtobed -i {input.bam} > $temp_file
-        fi
-
-
-        #compute number of fragments overlap peaks
-        mapReads=$(bedtools intersect -a $temp_file -b {input.bed} -wa -u | wc -l)
-
-        #compute number of mapped reads
-        totReads=$(samtools view -c -F 260 {input.bam})
-
-        #compute FRiP
-        totReads/mapReads
-
-        # plot_type: 'generalstats'
-        Sample  FRiP
-        H3K27ac_shCtrl  1.06
-        H3K27ac_shUbc9  1.14
-        Klf4_shCtrl 1.34
-        Klf4_shUbc9 1.19
-        """