# Display multiple files at once

## Basic method
Some datatset need to plot multiple files at once in order to get a synoptic view of an area. 

1. Primary menu → formulatAndIso, then Secondary menu → p = a or b
2. Primary menu → [file1] → [variable],  then Secondary menu → a → interp
3. Primary menu → [file2] → [variable],  then Secondary menu → b → interp

(symphonie-files)=
## Time frames over multiple files

If model outputs only contain one frame (as for SYMPHONIE), move from one file to another:
 1. Open all the files you need (on the open window, select all the files you want and confirm)
 2. Set up the variable you want on one file
 3. View window → display → scripts → next file [J] / previous file [K]

---
## Complex example for SWOT tracks

The following example use an more advance method to automaticaaly plot all the ascending or descending tracks of SWOT for a cycle and display them next to each other. To do so, we will need 2 files, one basic POCViP script and a more complex bash script that will build a dedicated POCViP script for each cycle and run it.

![SWOT cycle](../../_static/swot_cycle.jpg)

### 1. Setup appearance of the view (multiple_tracks.pocvip)

```bash
#set isolines
selectFile formulaAndIso/
selectVar p
setStatus isovalues{};flat=0.0;isolines{line{width=0.5;display="false";};}

#set the colormap as Constrasted Blue-Red
--palette colors={-3 #408 -2 #88f -1 #088 0 #fff 1 #fd0 2 #f88 3 #c00}

#set the projection
setView fi=0; la=-5.562;lo=125.335;zo=72.4060107; li=0
```

### 2a. Bash script to run POCViP in interactive mode

```bash
#/usr/bin

repo='/ctoh/share/data/alti_products/SWOT_Ocean/L3_KaRIn/v3_0/Expert_BandaSea_science/'
output_dir = $PWD/cycles
variable=ssha_unfiltered

#Set the wanted cycle and tracks
cycle="010"
odd=0  #0 for odd tracks (descending) and 1 for even tracks (ascending)

mkdir $output_dir

if [ $odd == 1 ];
    then tracks="ascending"
    else tracks="descending"
fi
    
echo "#######################" > tmp.pocvip
formula="p ="
n=0

echo "Add files to the list:"
for fichier in `cd $repo/cycle_$cycle/ ; ls * ; cd -` ; do
    if [[ "$fichier" =~ _([0-9]{3})_([0-9]{3})_ ]]; then
        c="${BASH_REMATCH[1]}"
        t="${BASH_REMATCH[2]}"

        # Verify the cycle and the track
        if [[ "$c" == "$cycle" ]] && [ $((10#$t % 2)) -eq $odd ]; then
            echo $fichier
            ((n = n + 1))

            #append the formula
            if [ $n -eq 1 ];then
                formula="$formula a$n"
            else
                formula="$formula or a$n"
            fi

            #append the pocvip script file with the attribution of all variable to plot
            echo "selectFile $repo/cycle_$cycle/$fichier" >> tmp.pocvip
            echo "selectVar $variable" >> tmp.pocvip
            echo "setStatus interpto=a$n" >> tmp.pocvip
            echo "#######################" >> tmp.pocvip

        fi
    fi
done

#merge appareance script with the script with all the tracks to plot
echo "#######################" > multiple_tracks.pocvip
echo "selectFile formulaAndIso/" >> multiple_tracks.pocvip
echo "setStatus $formula" >> multiple_tracks.pocvip
cat tmp.pocvip >> multiple_tracks.pocvip
echo "#######################" >> multiple_tracks.pocvip
cat multiple_tracks.pocvip.bckp >> multiple_tracks.pocvip

### run POCViP in interactive view 
    pocvip . multiple_tracks.pocvip
        
 ```

### 2b. Bash script to run POCViP recursively on all cycles

```bash
#/usr/bin

repo='/ctoh/share/data/alti_products/SWOT_Ocean/L3_KaRIn/v3_0/Expert_BandaSea_science/'
output_dir = $PWD/cycles
rootname=”Banda-”
variable=ssha_unfiltered

mkdir $output_dir

#loop on the ascending/descending trackes
for odd in "0" "1" ; do

    if [ $odd == 1 ];
        then tracks="ascending"
        else tracks="descending"
    fi
     
    #loop on the cycles
    for cycle in {001..032} ; do
        echo "#######################" > tmp.pocvip
        formula="p ="
        n=0

        echo "Add files to the list:"
        for fichier in `cd $repo/cycle_$cycle/ ; ls * ; cd -` ; do
            if [[ "$fichier" =~ _([0-9]{3})_([0-9]{3})_ ]]; then
                c="${BASH_REMATCH[1]}"
                t="${BASH_REMATCH[2]}"

                # Verify the cycle and the track
                if [[ "$c" == "$cycle" ]] && [ $((10#$t % 2)) -eq $odd ]; then
                    echo $fichier
                    ((n = n + 1))

                    #append the formula
                    if [ $n -eq 1 ];then
                        formula="$formula a$n"
                    else
                        formula="$formula or a$n"
                    fi

                    #append the pocvip script file with the attribution of all variable to plot
                    echo "selectFile $repo/cycle_$cycle/$fichier" >> tmp.pocvip
                    echo "selectVar $variable" >> tmp.pocvip
                    echo "setStatus interpto=a$n" >> tmp.pocvip
                    echo "#######################" >> tmp.pocvip

                fi
            fi
        done

        #merge appareance script with the script with all the tracks to plot
        echo "#######################" > multiple_tracks.pocvip
        echo "selectFile formulaAndIso/" >> multiple_tracks.pocvip
        echo "setStatus $formula" >> multiple_tracks.pocvip
        cat tmp.pocvip >> multiple_tracks.pocvip
        echo "#######################" >> multiple_tracks.pocvip
        cat multiple_tracks.pocvip.bckp >> multiple_tracks.pocvip

         ### for recursive plot of the each cycle
         echo "#######################" >> multiple_tracks.pocvip
         echo "renameView $output_dir/$rootname\cycle$cycle-$tracks.png" >> multiple_tracks.pocvip
         echo "printView 976 760" >> multiple_tracks.pocvip
         
         # run POCViP without interface (-x) process the script file (.) and quit afterward (-q)
         pocvip -x . multiple_tracks.pocvip -q
     done
 done
 ```