[KateEisenhower]

Hello OpenFOAM Users,

is there a quick and easy way to prevent OpenFOAM from creating a new time folder in the postProcessing directory after restarting a calculation?
For example I use functionObjects to write out forces in runtime. And I would like to have OF add the new data to the initial forces file instead.

Best regards and thank you for your help,

Kate

[floquation]

I never heard of that possibility.
Luckily, it is not too difficult to combine the files into a new file and work with it.
The script below is an excerpt from a larger script of mine that will do the job for you.

#! /usr/bin/sh
# @Author: Kevin van As; PhD Student; TU Delft - Transport Phenomena Research Group
# @Date: 30/01/2017
# Assumptions:
#   1. There is only one datafile within each time directory. Warning will print if this is not the case.
#   2. The time of the restart must be contained in the previous time's data file.
#      This is always the case in a restart.
#      In case this is not the case, the files will simply be merged without removing an eventual overlap.
# Changelog:
#   [30/01/2017] Creation.
#   [31/01/2017] Improved comments / error messages. $((lineNumber-1)) --> $((lineNumber))


args="${@}"

###################
#### FUNCTIONS ####
###################

usage () # prints a usage message. $1=error code (0 sends message to stdout, other number to errout)
{
    channelOut="2"
    if [ "$1" = "0" ]; then
        channelOut="1"
    fi

    echo \
    "
    Received input:
    '$0 $args'

    Usage: $0 args [> outputFile]
    " 1>&$channelOut


    echo \
    "
    Obligatory Arguments:
       -i : The directory name that holds multiple time directories. For example: \"./postProcessing/funcName\".
    Optional Arguments:
       -ro, --remove-overlap : Remove temporal data overlap [default behavior]
       -nro, --no-remove-overlap : Keep temporal data overlap
       -h, --h, -help, --help : Prints this message and quit
    " 1>&$channelOut

    exit $1
}

printerr () # echos a message to the error stream
{
    echo "$*" >&2
}


###############################
#### READ INPUT PARAMETERS ####
###############################

# Declare optional arguments with a default parameter
removeOverlap=true

# Iterate over arguments
while [ $# -gt 0 ]
do
    case "$1" in
        -i) parentDir="$2"; shift 2 ;;
        -ro | --remove-overlap) removeOverlap=true; shift ;;
        -nro | --no-remove-overlap) removeOverlap=false; shift ;;
        --help | -help | -h | --h) usage 0 ;;
        *) printerr ""
           printerr "ERROR: Unknown argument \"$1\""
           printerr ""
           usage 1 ;; # Unknown argument -> error
    esac
done
# Enforce obligatory arguments
[ "$parentDir" = "" ] && usage 1


###########################
#### THE ACTUAL SCRIPT ####
###########################

# Find the data:
cd "$parentDir" >/dev/null
    # Analyse structure of the directory
    timeDirs=(*) # Array of all time directories
    numTimeDirs="${#timeDirs[@]}"

    # Sort timeDirs numerically:
    IFS=$'\n' timeDirs=($(sort -g <<<"${timeDirs[*]}"))
    unset IFS

    #echo "timeDirs=${timeDirs[@]}"

    # Now start combining data files
    #echo "Matching lines..."
    timeDirCounter=0
    for timeDir in ${timeDirs[@]} # Iterate over timeDirs to combine the files
    do
        #echo "  Time: $timeDir"
        timeDirCounter=$((timeDirCounter+1))

        time=${timeDirs[$timeDirCounter]} # The name of the next timedir is the "cut-off" point for the datafile of the current timedir. Note: it is blank "" for the last timedir.
        #echo "   Find time = $time"
        dataFiles=("$timeDir"/*) #TODO: Iterate over datafiles inside the timedir (just in case there are multiple)?
        dataFile="${dataFiles[0]}"
        if [ "${#dataFiles[@]}" -gt 1 ]; then
            printerr ""
            printerr "WARNING:"
            printerr "  This code assumes there is only one dataFile inside each time directory, but ${#dataFiles[@]} were found!"
            printerr "  These are: ${dataFiles[@]}"
            printerr "  The code will continue using only the first dataFile: $(basename $dataFile)"
            printerr ""
        fi

        #echo "    Datafile: $dataFile"

        # Print header if first.
        if [ "$timeDirCounter" = 1 ]; then
            cat "$dataFile" | head -1
        fi

        # This is the last file, treat it differently.
        if [ "$time" == "" ]; then
            cat "$dataFile" | tail -n +2
            break
        fi

        # For all other files, scan the overlap, and then print the relevant part
        if [ "$removeOverlap" = true ]; then # Disallow overlap
            timeLine=`grep -n -P -o "^\s*$time\s+" "$dataFile" | head -1 | tail -1`;
            theTime=`echo "$timeLine" | sed 's/.*://' | sed 's/\s//g'` # for sanity check
            lineNumber=`echo "$timeLine" | sed 's/:.*//'` # for 'head'
            #echo "theTime=$theTime"
            #echo "lineNumber=$lineNumber"

            if [ "$timeLine" = "" ]; then # There is no overlap between files!
                cat "$dataFile" | tail -n +2
                continue
            fi

            if [ "$theTime" != "$time" ]; then # sanity-check
                printerr "FATAL ERROR"
                printerr "  ERROR IN CODE LOGIC (probably the regex): SANITY CHECK FAILED: FIRSTNUMBER \"$theTime\" IS NOT EQUAL TO TIME \"$time\""
                exit
            fi

            # All is OK, so output the relevant part of $dataFile: before $time, but without header
            cat "$dataFile" | head -$((lineNumber)) | tail -n +2
            continue
        else # Allow overlap, so just cat the file.
            cat "$dataFile" | tail -n +2
            continue
        fi

        #echo "  timeDir(\"$timeDir\") read. Next file."
    done # timeDir
cd - >/dev/null



## Done!